Wireless power transmitter and method of wireless power transmission

ABSTRACT

The present disclosure relates to a wireless power transmitter capable of reducing standby power in the wireless power transmitter, and a method thereof, and the wireless power transmitter according to the present disclosure may include a power supply unit configured to supply a voltage; a receiving unit configured to receive a power-on signal or power-off signal from a remote controller; a power transmission controller configured to generate a drive signal to supply power for the operation of the electronic device based on the power-on signal; and a power transmission unit configured to form a wireless power signal based on the supplied voltage and the drive signal to transmit wireless power to the wireless power receiver.

RELATED APPLICATION

This application claims the benefit of priority to Korean PatentApplication No. 10-2013-0077889, filed on Jul. 3, 2013, the contents ofwhich is herein expressly incorporated by reference in its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present disclosure relates to a wireless power transmitter, and amethod thereof.

2. Description of the Related Art

In recent years, the method of contactlessly supplying electrical energyto electronic devices in a wireless manner has been used instead of thetraditional method of supplying electrical energy in a wired manner. Theelectronic device receiving energy in a wireless manner may be directlydriven by the received wireless power, or a battery may be charged byusing the received wireless power so as to allow the electronic deviceto be driven by the charged power.

The Wireless Power Consortium dealing with technologies for magneticinduction type wireless power transfer released a standard document“System description Wireless Power Transfer, Volume 1, Low Power, Part1: Interface Definition, Version 1.00 Release Candidate 1 (RC1)” forinteroperability in the wireless power transfer on Apr. 12, 2010. Thestandard document of the Wireless Power Consortium describes a scheme oftransferring power from a wireless power transmitter to a wireless powerreceiver in a magnetic induction mode.

SUMMARY OF THE INVENTION

An aspect of the present disclosure is to provide a wireless powertransmitter capable of reducing standby power in the wireless powertransmitter, and a method thereof.

According to the present disclosure, there is provided a wireless powertransmitter for transmitting wireless power to an electronic device towhich a wireless power receiver is applied, and the wireless powertransmitter may include a power supply unit configured to supply anvoltage; a receiving unit configured to receive a power-on signal orpower-off signal from a remote controller; a power transmissioncontroller configured to generate a drive signal to supply power for theoperation of the electronic device based on the power-on signal; and apower transmission unit configured to form a wireless power signal basedon the supplied voltage and the drive signal to transmit wireless powerto the wireless power receiver.

As an example associated with the present disclosure, the receiving unitmay turn off the wireless power transmitter excluding the receiving unitbased on the power-off signal.

As an example associated with the present disclosure, the receiving unitmay receive power from a power supply unit which is independent from thepower supply unit.

As an example associated with the present disclosure, the wireless powertransmitter may further include a sub-power supply unit configured toapply low power used in the receiving unit.

As an example associated with the present disclosure, the wireless powertransmitter may further include a sub-power supply unit configured togenerate wireless low power based on the supplied voltage, and apply thegenerated wireless low power to the receiving unit.

As an example associated with the present disclosure, the wireless powertransmitter may further include a sub-power supply unit configured toconvert the supplied voltage to a low voltage, and form a wireless lowpower signal based on the converted low voltage and a low power drivesignal for the operation of the receiving unit to generate wireless lowpower, and apply the generated wireless low power to the receiving unit.

As an example associated with the present disclosure, the receiving unitmay receive a power-on signal or power-off signal from the remotecontroller based on the wireless low power applied from the sub-powersupply unit.

As an example associated with the present disclosure, the sub-powersupply unit may include a low power transmission controller configuredto generate a low power drive signal to supply low power for theoperation of the receiving unit; a low power transmission unitconfigured to convert the voltage supplied from the power supply unit toa low voltage, and form a wireless low power signal based on theconverted low voltage and the low power drive signal to transmitwireless low power; and a low power receiving unit configured to receivethe wireless low power transmitted from the low power transmission unit,and apply the received wireless low power to the receiving unit.

As an example associated with the present disclosure, the powertransmission controller may adjust a transmission rate of the wirelesspower according to the power usage of the electronic device.

As an example associated with the present disclosure, the receiving unitmay include a charging device configured to charge the wireless poweroutput from the wireless power receiver, and supply the charged power tothe receiving unit for a period of time in which the wireless powertransmitter is turned off.

According to the present disclosure, there is provided a wireless powertransmission method for transmitting wireless power to an electronicdevice to which the wireless power transmitter is applied, and themethod may include receiving a power-on signal or power-off signal froma remote controller through a receiving unit; generating a drive signalto supply power for the operation of the electronic device based on thepower-on signal; and forming a wireless power is signal based on aninput voltage and the drive signal to transmit wireless power to thewireless power receiver.

According to the present disclosure, there is provided an electronicdevice having a wireless power receiver, and the electronic device mayinclude a signal receiving unit configured to receive a power-on signalor power-off signal from a remote controller; a power receivingcontroller configured to request the supply of wireless power to thewireless power transmitter based on the power-on signal; and a powerreceiving unit configured to receive wireless power transmitted inresponse to the request from the wireless power transmitter to performthe power-on of the electronic device.

As an example associated with the present disclosure, the signalreceiving unit is formed to receive low power having a size less thanthat of the wireless power which is transmitted from the wireless powertransmitter.

A wireless power transmission system according to the present disclosuremay include an electronic device and a wireless power transmitter fortransmitting wireless power to the electronic device, and the wirelesspower transmitter may include a power supply unit configured to supply avoltage; a receiving unit configured to receive a power-on signal orpower-off signal from a remote controller; and a power transmissioncontroller configured to transmit the wireless power to the electronicdevice based on the power-on signal, wherein the electronic devicereceives the wireless power to turn on power.

A wireless power transmission system according to the present disclosuremay include an electronic device and a wireless power transmitter fortransmitting wireless power to the electronic device, and the electronicdevice may include a signal receiving unit configured to receive apower-on signal or power-off signal from a remote controller; and apower receiving controller configured to request the supply of wirelesspower to the wireless power transmitter based on the power-on signal,wherein the wireless power transmitter includes a power supply unitconfigured to supply an input voltage; and a power transmissioncontroller configured to generate a drive signal to supply the wirelesspower to the electronic device based on the request.

A wireless power transmitter and a method thereof according to anembodiment of the present disclosure, only a receiving unit forreceiving a power-on/off signal may be turned on when an electronicdevice to which a wireless power receiver is applied is turned off,thereby reducing the standby power of the wireless power transmitter andthe electronic device. For example, only the consumption power of thereceiving unit in the wireless power transmitter may be used when theelectronic device is not used, thereby reducing the standby power of thewireless power transmitter and the standby power of the electronicdevice.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the invention and are incorporated in and constitute apart of this specification, illustrate embodiments of the invention andtogether with the description serve to explain the principles of theinvention.

In the drawings:

FIG. 1 is an exemplary view conceptually illustrating a wireless powertransmitter and an electronic device according to the embodiments of thepresent invention;

FIGS. 2A and 2B are exemplary block diagrams illustrating theconfiguration of a wireless power transmitter and an electronic devicethat can be employed in the embodiments disclosed herein, respectively;

FIG. 3 is a view illustrating a concept in which power is transferredfrom a wireless power transmitter to an electronic device in a wirelessmanner according to an inductive coupling method;

FIG. 4A and FIG. 4B are block diagrams illustrating part of a wirelesspower transmitter and an electronic device in a magnetic inductionmethod that can be employed in the embodiments disclosed herein;

FIG. 5 is a block diagram illustrating a wireless power transmitterconfigured to have one or more transmission coils receiving poweraccording to an inductive coupling method that can be employed in theembodiments disclosed herein;

FIG. 6 is a view illustrating a concept in which power is transferred toan electronic device from a wireless power transmitter in a wirelessmanner according to a resonance coupling method;

FIG. 7A and FIG. 7B are block diagrams exemplarily illustrating part ofa wireless power transmitter and an electronic device in a resonancemethod that can be employed in the embodiments disclosed herein;

FIG. 8 is a block diagram illustrating a wireless power transmitterconfigured to have one or more transmission coils receiving poweraccording to a resonance coupling method that can be employed in theembodiments disclosed herein;

FIG. 9 is a block diagram illustrating a wireless power transmitterfurther including an additional element in addition to the configurationillustrated in FIG. 2A;

FIG. 10 is view illustrating a configuration in case where an electronicdevice according to the embodiments disclosed herein is implemented inthe form of a mobile terminal;

FIG. 11A and FIG. 11B are view illustratings the concept of transmittingand receiving a packet between a wireless power transmitter and anelectronic device through the modulation and demodulation of a wirelesspower signal in wireless power transfer disclosed herein;

FIG. 12 is a view illustrating a method of showing data bits and byteconstituting a power control message provided by the wireless powertransmitter 100;

FIG. 13 is a view illustrating a packet including a power controlmessage used in a wireless power transfer method according to theembodiments disclosed herein;

FIG. 14 is a view illustrating the operation phases of a wireless powertransmitter and an electronic device according to the embodimentsdisclosed herein;

FIGS. 15 through 19 are views illustrating the structure of packetsincluding a power control message between the wireless power transmitterand electronic device;

FIG. 20 is a configuration diagram illustrating a wireless powertransmitter for reducing standby power according to an embodiment of thepresent disclosure;

FIG. 21 is a flow chart illustrating a wireless power transmissionmethod for reducing standby power according to an embodiment of thepresent disclosure;

FIG. 22 is a configuration diagram illustrating a wireless powertransmitter for reducing standby power according to another embodimentof the present disclosure;

FIG. 23 is a configuration diagram illustrating a sub-power supply unitaccording to another embodiment of the present disclosure; and

FIG. 24 is a flow chart illustrating a wireless power transmissionmethod for reducing standby power according to another embodiment of thepresent disclosure.

DETAILED DESCRIPTION OF THE INVENTION

The technologies disclosed herein may be applicable to wireless powertransfer (contactless power transfer). However, the technologiesdisclosed herein are not limited to this, and may be also applicable toall kinds of power transmission systems and methods, wireless chargingcircuits and methods to which the technological spirit of the technologycan be applicable, in addition to the methods and apparatuses usingpower transmitted in a wireless manner.

It should be noted that technological terms used herein are merely usedto describe a specific embodiment, but not to limit the presentinvention. Also, unless particularly defined otherwise, technologicalterms used herein should be construed as a meaning that is generallyunderstood by those having ordinary skill in the art to which theinvention pertains, and should not be construed too broadly or toonarrowly.

Furthermore, if technological terms used herein are wrong terms unableto correctly express the spirit of the invention, then they should bereplaced by technological terms that are properly understood by thoseskilled in the art. In addition, general terms used in this inventionshould be construed based on the definition of dictionary, or thecontext, and should not be construed too broadly or too narrowly.

Incidentally, unless clearly used otherwise, expressions in the singularnumber include a plural meaning. In this application, the terms“comprising” and “including” should not be construed to necessarilyinclude all of the elements or steps disclosed herein, and should beconstrued not to include some of the elements or steps thereof, orshould be construed to further include additional elements or steps.

In addition, a suffix “module” or “unit” used for constituent elementsdisclosed in the following description is merely intended for easydescription of the specification, and the suffix itself does not giveany special meaning or function.

Furthermore, the terms including an ordinal number such as first,second, etc. can be used to describe various elements, but the elementsshould not be limited by those terms. The terms are used merely for thepurpose to distinguish an element from the other element. For example, afirst element may be named to a second element, and similarly, a secondelement may be named to a first element without departing from the scopeof right of the invention.

Hereinafter, preferred embodiments of the present invention will bedescribed in detail with reference to the accompanying drawings, and thesame or to similar elements are designated with the same numeralreferences regardless of the numerals in the drawings and theirredundant description will be omitted.

In describing the present invention, moreover, the detailed descriptionwill be omitted when a specific description for publicly knowntechnologies to which the invention pertains is judged to obscure thegist of the present invention. Also, it should be noted that theaccompanying drawings are merely illustrated to easily explain thespirit of the invention, and therefore, they should not be construed tolimit the spirit of the invention by the accompanying drawings.

FIG. 1 is an exemplary view conceptually illustrating a wireless powertransmitter and an electronic device according to the embodiments of thepresent invention.

Referring to FIG. 1, the wireless power transmitter 100 may be a powertransfer apparatus configured to transfer power required for theelectronic device 200 in a wireless manner.

Accordingly, the electronic device 200 may be a wireless power receiver.

Furthermore, the wireless power transmitter 100 may be a wirelesscharging apparatus configured to charge a battery of the electronicdevice 200 by transferring power in a wireless manner. A case where thewireless power transmitter 100 is a wireless charging apparatus will bedescribed later with reference to FIG. 9.

Additionally, the wireless power transmitter 100 may be implemented withvarious forms of apparatuses transferring power to the electronic device200 requiring power in a contactless state.

The electronic device 200 is a device that is operable by receivingpower from the wireless power transmitter 100 in a wireless manner.Furthermore, the to electronic device 200 may charge a battery using thereceived wireless power.

On the other hand, an electronic device for receiving power in awireless manner as described herein should be construed broadly toinclude a portable phone, a cellular phone, a smart phone, a personaldigital assistant (PDA), a portable multimedia player (PMP), a tablet, amultimedia device, or the like, in addition to an input/output devicesuch as a keyboard, a mouse, an audio-visual auxiliary device, and thelike.

The electronic device 200, as described later, may be a mobilecommunication terminal, (for example, a portable phone, a cellularphone, and a tablet or multimedia device). In case where the electronicdevice is a mobile terminal, it will be described later with referenceto FIG. 10.

On the other hand, the wireless power transmitter 100 may transfer powerin a wireless manner without mutual contact to the electronic device 200using one or more wireless power transfer methods. In other words, thewireless power transmitter 100 may transfer power using at least one ofan inductive coupling method based on magnetic induction phenomenon bythe wireless power signal and a magnetic resonance coupling method basedon electromagnetic resonance phenomenon by a wireless power signal at aspecific frequency.

Wireless power transfer in the inductive coupling method is a technologytransferring power in a wireless manner using a primary coil and asecondary coil, and refers to the transmission of power by inducing acurrent from a coil to another coil through a changing magnetic field bya magnetic induction phenomenon.

Wireless power transfer in the inductive coupling method refers to atechnology in which the electronic device 200 generates resonance by awireless power signal transmitted from the wireless power transmitter100 to transfer power to from the wireless power transmitter 100 to thewireless power receiver 200 by the resonance phenomenon.

Hereinafter, the wireless power transmitter 100 and electronic device200 according to the embodiments disclosed herein will be described indetail. In assigning reference numerals to the constituent elements ineach of the following drawings, the same reference numerals will be usedfor the same constituent elements even though they are shown in adifferent drawing.

FIG. 2 is an exemplary block diagram illustrating the configuration of awireless power transmitter 100 and an electronic device 200 that can beemployed in the embodiments disclosed herein.

Referring to FIG. 2A, the wireless power transmitter 100 may include apower transmission unit 110. The power transmission unit 110 may includea power transmission unit 111 and a power transmission control unit 112.

The power transmission unit 111 transfers power supplied from atransmission side power supply unit 190 to the electronic device 200 byconverting it into a wireless power signal. The wireless power signaltransferred by the power transmission unit 111 is generated in the formof a magnetic field or electromagnetic field having an oscillationcharacteristic. For this purpose, the power transmission unit 111 may beconfigured to include a coil for generating the wireless power signal.

The power transmission unit 111 may include a constituent element forgenerating a different type of wireless power signal according to eachpower transfer method.

According to some embodiments, the power transmission unit 111 mayinclude a primary coil for forming a changing magnetic field to induce acurrent to a secondary coil of the electronic device 200. Furthermore,the power transmission unit 111 may include a coil (or antenna) forforming a magnetic field having a specific resonant frequency togenerate a resonant frequency in the electronic device 200 according tothe resonance coupling method.

Furthermore, according to some embodiments, the power transmission unit111 may transfer power using at least one of the foregoing inductivecoupling method and the resonance coupling method.

Among the constituent elements included in the power transmission unit111, those for the inductive coupling method will be described laterwith reference to FIGS. 4 and 5, and those for the resonance couplingmethod will be described with reference to FIGS. 7 and 8.

On the other hand, the power transmission unit 111 may further include acircuit for controlling the characteristics of a used frequency, anapplied voltage, an applied current or the like to form the wirelesspower signal.

The power transmission control unit 112 controls each of the constituentelements included in the power transmission unit 110 The powertransmission control unit 112 may be implemented to be integrated intoanother control unit (not shown) for controlling the wireless powertransmitter 100.

On the other hand, a region to which the wireless power signal can beapproached may be divided into two types. First, an active area denotesa region through which a wireless power signal transferring power to theelectronic device 200 is passed. Next, a semi-active area denotes aninterest region in which the wireless power transmitter 100 can detectthe existence of the electronic device 200. Here, the power transmissioncontrol unit 112 may detect whether the electronic device 200 is placedin the active area or detection area or removed from the area.Specifically, the power transmission control unit 112 may detect whetheror not the electronic device 200 is placed in the active area ordetection area using a wireless power signal formed from the powertransmission unit 111 or a sensor separately provided therein. Forinstance, the power transmission control unit 112 may detect thepresence of the electronic device 200 by monitoring is whether or notthe characteristic of power for forming the wireless power signal ischanged by the wireless power signal, which is affected by theelectronic device 200 existing in the detection area. However, theactive area and detection area may vary according to the wireless powertransfer method such as an inductive coupling method, a resonancecoupling method, and the like.

The power transmission control unit 112 may perform the process ofidentifying the electronic device 200 or determine whether to startwireless power transfer according to a result of detecting the existenceof the electronic device 200.

Furthermore, the power transmission control unit 112 may determine atleast one characteristic of a frequency, a voltage, and a current of thepower transmission unit 111 for forming the wireless power signal. Thedetermination of the characteristic may be carried out by a condition atthe side of the wireless power transmitter 100 or a condition at theside of the electronic device 200. In exemplary embodiments, the powertransmission control unit 112 may decide the characteristic based ondevice identification information. In another exemplary embodiment, thepower transmission control unit 112 may decide the characteristic basedon required power information of the electronic device 200 or profileinformation related to the required power. The power transmissioncontrol unit 112 may receive a power control message from the electronicdevice 200. The power transmission control unit 112 may determine atleast one characteristic of a frequency, a voltage and a current of thepower transmission unit 111 based on the received power control message,and additionally perform other control operations based on the powercontrol message.

For example, the power transmission control unit 112 may determine at isleast one characteristic of a frequency, a voltage and a current used toform the wireless power signal according to the power control messageincluding at least one of rectified power amount information, chargingstate information and identification information in the electronicdevice 200.

The power transmission control unit 112 may execute scanning offrequencies within a preset range by controlling the power transmissionunit 111, in order to acquire frequency-based power transfer informationrelating to wireless power receivers which are located within the activearea or the semi-active area.

The scanning refers to an operation or method of checking the changes ofthe power transfer information in response to the change of a frequencyof a wireless power signal. For example, the scanning may refer to anoperation in which the wireless power transmitter 100 sequentiallytransmits wireless power signals having different frequencies andreceives power transfer information corresponding to each of thesequentially-transmitted wireless power signals.

The power transfer information may include information related to atleast one of a receiving-side voltage of the wireless power receiver, areceiving-side current of the wireless power receiver, a first referencevoltage and a second reference voltage.

Here, the first reference voltage may be decided based on whether or notit is a voltage which is likely to cause damage on the wireless powerreceiver. The second reference voltage may be decided based on whetheror not it is a voltage to receive power from the wireless powertransmitter in a wireless manner.

Furthermore, as another control operation using the power controlmessage, the wireless power transmitter 100 may perform a typicalcontrol operation associated with wireless power transfer based on thepower control message. For example, the wireless power transmitter 100may receive information associated with the electronic device 200 to beauditorily or visually outputted through the power control message, orreceive information required for authentication between devices.

According to some embodiments, the power transmission control unit 112may receive the power control message through the wireless power signal.In other exemplary embodiment, the power transmission control unit 112may receive the power control message through a method for receivinguser data.

In order to receive the foregoing power control message, the wirelesspower transmitter 100 may further include a modulation/demodulation unit113 electrically connected to the power transmission unit 111. Themodulation/demodulation unit 113 may modulate a wireless power signalthat has been modulated by the electronic device 200 and use it toreceive the power control message. The method for allowing the powertransmission unit 111 to receive a power control message using awireless power signal will be described later with reference to FIGS. 11through 13.

In addition, the power transmission control unit 112 may acquire a powercontrol message by receiving user data including a power control messageby a communication means (not shown) included in the wireless powertransmitter 100.

FIG. 2B—Electronic device

Referring to FIG. 2B, the electronic device 200 may include a powersupply unit 290. The power supply unit 290 supplies power required forthe operation of the electronic device 200. The power supply unit 290may include a power receiving unit 291 and a power reception controlunit (or POWER RECEIVING CONTROL UNIT) 292.

The power receiving unit 291 receives power transferred from thewireless power transmitter 100 in a wireless manner.

The power receiving unit 291 may include constituent elements requiredto receive the wireless power signal according to a wireless powertransfer method. Furthermore, the power receiving unit 291 may receivepower according to at least one wireless power transfer method, and inthis case, the power receiving unit 291 may include constituent elementsrequired for each method.

First, the power receiving unit 291 may include a coil for receiving awireless power signal transferred in the form of a magnetic field orelectromagnetic field having a vibration characteristic.

For instance, according to some embodiments, as a constituent elementaccording to the inductive coupling method, the power receiving unit 291may include a secondary coil to which a current is induced by a changingmagnetic field. Furthermore, according to some embodiments, the powerreceiving unit 291, as a constituent element according to the resonancecoupling method, may include a coil and a resonant circuit in whichresonance phenomenon is generated by a magnetic field having a specificresonant frequency.

However, according to some embodiments, when the power receiving unit291 receives power according to at least one wireless power transfermethod, the power receiving unit 291 may be implemented to receive powerby using a coil, or to implemented to receive power by using a coilformed differently according to each power transfer method.

Among the constituent elements included in the power receiving unit 291,those for the inductive coupling method will be described later withreference to FIG. 4A and FIG. 4B, and those for the resonance couplingmethod with reference to FIG. 7A and FIG. 7B.

On the other hand, the power receiving unit 291 may further include arectifier and a regulator to convert the wireless power signal into adirect current. Furthermore, the power receiving unit 291 may furtherinclude a circuit for protecting an overvoltage or overcurrent frombeing generated by the received power signal.

The power receiving control unit 292 may control each constituentelement included in the power supply unit 290.

Specifically, the power receiving control unit 292 may transfer a powercontrol message to the wireless power transmitter 100. The power controlmessage may instruct the wireless power transmitter 100 to initiate orterminate a transfer of the wireless power signal. Furthermore, thepower control message may instruct the wireless power transmitter 100 tocontrol a characteristic of the wireless power signal.

According to some embodiments, the power receiving control unit 292 maytransmit the power control message through the wireless power signal. Inanother exemplary embodiment, the power receiving control unit 292 maytransmit the power control message through a method for transmittinguser data.

In order to transmit the foregoing power control message, the electronicdevice 200 may further include a modulation/demodulation unit 293electrically connected to the power receiving unit 291. Themodulation/demodulation unit 293, similarly to the case of the wirelesspower transmitter 100, may be used to transmit the power control messagethrough the wireless power signal. The modulation/demodulation unit 293may be used as a means for controlling a current and/or voltage flowingthrough the power transmission unit 111 of the wireless powertransmitter 100. Hereinafter, a method for allowing themodulation/demodulation unit 113 or 293 at the side of the wirelesspower transmitter 100 and at the side of the electronic device 200,respectively, to be used to transmit and receive a power control messagethrough a wireless power signal will be described.

A wireless power signal formed by the power transmission unit 111 isreceived by the power receiving unit 291. At this time, the powerreceiving control unit 292 controls the modulation/demodulation unit 293at the side of the electronic device 200 to modulate the wireless powersignal. For instance, the power receiving control unit 292 may perform amodulation process such that a power amount received from the wirelesspower signal is varied by changing a reactance of themodulation/demodulation unit 293 connected to the power receiving unit291. The change of a power amount received from the wireless powersignal results in the change of a current and/or voltage of the powertransmission unit 111 for forming the wireless power signal. At thistime, the modulation/demodulation unit 113 at the side of the wirelesspower transmitter 100 may detect a change of the current and/or voltageto perform a demodulation process.

In other words, the power receiving control unit 292 may generate apacket including a power control message intended to be transferred tothe wireless power transmitter 100 and modulate the wireless powersignal to allow the packet to be included therein, and the powertransmission control unit 112 may decode the packet based on a result ofperforming the demodulation process of the modulation/demodulation unit113 to acquire the power control message included in the packet. Thedetailed method of allowing the wireless power transmitter 100 toacquire the power control message will be described later with referenceto FIGS. 11 through 13.

In addition, the power receiving control unit 292 may transmit a powercontrol message to the wireless power transmitter 100 by transmittinguser data including the power control message by a communication means(not shown) included in the electronic device 200.

In addition, the power supply unit 290 may further include a charger 298and a battery 299.

The electronic device 200 receiving power for operation from the powersupply unit 290 may be operated by power transferred from the wirelesspower transmitter 100, or operated by charging the battery 299 using thetransferred power and then receiving the charged power. At this time,the power receiving control unit 292 may control the charger 298 toperform charging using the transferred power.

Hereinafter, a wireless power transmitter and an electronic deviceapplicable to the embodiments disclosed herein will be described.

First, a method of allowing the wireless power transmitter to transferpower to the electronic device according to the inductive couplingmethod will be described with reference to FIGS. 3 through 5.

FIG. 3 is a view illustrating a concept in which power is transferredfrom a wireless power transmitter to an electronic device in a wirelessmanner according to an inductive coupling method.

When the power of the wireless power transmitter 100 is transferred inan inductive coupling method, if the strength of a current flowingthrough a primary coil within the power transmission unit 110 ischanged, then a magnetic field passing through the primary coil may bechanged by the current. The changed magnetic field generates an inducedelectromotive force at a secondary coil in the electronic device 200.

According to the foregoing method, the power transmission unit 111 ofthe wireless power transmitter 100 may include a transmitting (Tx) coil1111 a being operated as a primary coil in magnetic induction.Furthermore, the power receiving unit 291 of the electronic device 200may include a receiving (Rx) coil 2911 a being operated as a secondarycoil in magnetic induction.

First, the wireless power transmitter 100 and electronic device 200 aredisposed in such a manner that the transmitting coil 1111 a at the sideof the wireless power transmitter 100 and the receiving coil at the sideof the electronic device 200 are located adjacent to each other. Then,if the power transmission control unit 112 controls a current of thetransmitting coil 1111 a to be changed, then the power receiving unit291 controls power to be supplied to the electronic device 200 using anelectromotive force induced to the receiving coil 2911 a.

The efficiency of wireless power transfer by the inductive couplingmethod may be little affected by a frequency characteristic, butaffected by an alignment and distance between the wireless powertransmitter 100 and the electronic device 200 including each coil.

On the other hand, in order to perform wireless power transfer in theinductive coupling method, the wireless power transmitter 100 may beconfigured to include an interface surface (not shown) in the form of aflat surface. One or more electronic devices may be placed at an upperportion of the interface surface, and the transmitting coil 1111 a maybe mounted at a lower portion of the interface surface. In this case, avertical spacing is formed in a small-scale between the transmittingcoil 1111 a mounted at a lower portion of the interface surface and thereceiving coil 2911 a of the electronic device 200 placed at an upperportion of the interface surface, and thus a distance between the coilsbecomes sufficiently small to efficiently implement contactless powertransfer by the inductive coupling method.

Furthermore, an alignment indicator (not shown) indicating a locationwhere the electronic device 200 is to be placed at an upper portion ofthe interface surface. The alignment indicator indicates a location ofthe electronic device 200 where an alignment between the transmittingcoil 1111 a mounted at a lower portion of the interface surface and thereceiving coil 2911 a can be suitably implemented. The alignmentindicator may alternatively be simple marks, or may be formed in theform of a protrusion structure for guiding the location of theelectronic device 200. Otherwise, the alignment indicator may be formedin the form of a magnetic body such as a magnet mounted at a lowerportion of the interface surface, thereby guiding the coils to besuitably arranged by mutual magnetism to a magnetic body having anopposite polarity mounted within the electronic device 200.

On the other hand, the wireless power transmitter 100 may be formed toinclude one or more transmitting coils. The wireless power transmitter100 may selectively use some of coils suitably arranged with thereceiving coil 2911 a of the electronic device 200 among the one or moretransmitting coils to enhance the to power transmission efficiency. Thewireless power transmitter 100 including the one or more transmittingcoils will be described later with reference to FIG. 5.

Hereinafter, a configuration of the wireless power transmitter andelectronic device using an inductive coupling method applicable to theembodiments disclosed herein will be described in detail.

FIG. 4A and FIG. 4B are block diagrams illustrating part of the wirelesspower transmitter 100 and the electronic device 200 in a magneticinduction method that can be employed in the embodiments disclosedherein. A configuration of the power transmission unit 110 included inthe wireless power transmitter 100 will be described with reference toFIG. 4A, and a configuration of the power supply unit 290 included inthe electronic device 200 will be described with reference to FIG. 4B.

Referring to FIG. 4A, the power transmission unit 111 of the wirelesspower transmitter 100 may include a transmitting (Tx) coil 1111 a and aninverter 1112.

The transmitting coil 1111 a may form a magnetic field corresponding tothe wireless power signal according to a change of current as describedabove. The transmitting coil 1111 a may alternatively be implementedwith a planar spiral type or cylindrical solenoid type.

The inverter 1112 transforms a DC input obtained from the power supplyunit 190 into an AC waveform. The AC current transformed by the inverter1112 drives a resonant circuit including the transmitting coil 1111 aand a capacitor (not shown) to form a magnetic field in the transmittingcoil 1111 a. In response to the formation of the magnetic field, thewireless power signal may be transferred from the wireless powertransmitter 100 to the wireless power receiver 200.

In accordance with one exemplary embodiment, the AC waveform generatedfrom the inverter 1112 may be a carrier signal, which may drive aresonant circuit such that the wireless power signal can be generatedfrom the transmitting coil 1111 a. That is, the wireless power signalmay be generated based on the carrier signal.

In addition, the power transmission unit 111 may further include apositioning unit 1114.

The positioning unit 1114 may move or rotate the transmitting coil 1111a to enhance the effectiveness of contactless power transfer using theinductive coupling method. As described above, it is because analignment and distance between the wireless power transmitter 100 andthe electronic device 200 including a primary coil and a secondary coilmay affect power transfer using the inductive coupling method. Inparticular, the positioning unit 1114 may be used when the electronicdevice 200 does not exist within an active area of the wireless powertransmitter 100.

Accordingly, the positioning unit 1114 may include a drive unit (notshown) for moving the transmitting coil 1111 a such that acenter-to-center distance of the transmitting coil 1111 a of thewireless power transmitter 100 and the receiving coil 2911 a of theelectronic device 200 is within a predetermined range, or rotating thetransmitting coil 1111 a such that the centers of the transmitting coil1111 a and the receiving coil 2911 a are overlapped with each other.

For this purpose, the wireless power transmitter 100 may further includea detection unit (not shown) made of a sensor for detecting the locationof the electronic device 200, and the power transmission control unit112 may control the positioning unit 1114 based on the locationinformation of the electronic device 200 to received from the locationdetection sensor.

Furthermore, to this end, the power transmission control unit 112 mayreceive control information on an alignment or distance to theelectronic device 200 through the modulation/demodulation unit 113, andcontrol the positioning unit 1114 based on the received controlinformation on the alignment or distance.

If the power transmission unit 111 is configured to include a pluralityof transmitting coils, then the positioning unit 1114 may determinewhich one of the plurality of transmitting coils is to be used for powertransmission. The configuration of the wireless power transmitter 100including the plurality of transmitting coils will be described laterwith reference to FIG. 5.

On the other hand, the power transmission unit 111 may further include apower sensing unit 1115. The power sensing unit 1115 at the side of thewireless power transmitter 100 monitors a current or voltage flowinginto the transmitting coil 1111 a. The power sensing unit 1115 isprovided to check whether or not the wireless power transmitter 100 isnormally operated, and thus the power sensing unit 1115 may detect avoltage or current of the power supplied from the outside, and checkwhether the detected voltage or current exceeds a threshold value. Thepower sensing unit 1115, although not shown, may include a resistor fordetecting a voltage or current of the power supplied from the outsideand a comparator for comparing a voltage value or current value of thedetected power with a threshold value to output the comparison result.Based on the check result of the power sensing unit 1115, the powertransmission control unit 112 may control a switching unit (not shown)to cut off power applied to the transmitting coil 1111 a.

Referring to FIG. 4B, the power supply unit 290 of the electronic device200 may include a receiving (Rx) coil 2911 a and a rectifier generationcircuit 2913.

A current is induced into the receiving coil 2911 a by a change of themagnetic field formed in the transmitting coil 1111 a. Theimplementation type of the receiving coil 2911 a may be a planar spiraltype or cylindrical solenoid type similarly to the transmitting coil1111 a.

Furthermore, series and parallel capacitors may be configured to beconnected to the receiving coil 2911 a to enhance the effectiveness ofwireless power reception or perform resonant detection.

The receiving coil 2911 a may be in the form of a single coil or aplurality of coils.

The rectifier circuit 2913 performs a full-wave rectification to acurrent to convert alternating current into direct current. Therectifier circuit 2913, for instance, may be implemented with afull-bridge rectifier generation circuit made of four diodes or acircuit using active components.

In addition, the rectifier circuit 2913 may further include a regulatorcircuit for converting a rectified current into a more flat and stabledirect current. Furthermore, the output power of the rectifier circuit2913 is supplied to each constituent element of the power supply unit290. Furthermore, the rectifier circuit 2913 may further include a DC-DCconverter for converting output DC power into a suitable voltage toadjust it to the power required for each constituent element (forinstance, a circuit such as a charger 298).

The modulation/demodulation unit 293 may be connected to the powerreceiving unit 291, and may be configured with a resistive element inwhich resistance varies with respect to direct current, and may beconfigured with a capacitive element in which reactance varies withrespect to alternating current. The power receiving control unit 292 maychange the resistance or reactance of the power communicationsmodulation/demodulation unit 293 to modulate a wireless power signalreceived to the power receiving unit 291.

On the other hand, the power supply unit 290 may further include a powersensing unit 2914. The power sensing unit 2914 at the side of theelectronic device 200 monitors a voltage and/or current of the powerrectified by the rectifier circuit 2913, and if the voltage and/orcurrent of the rectified power exceeds a threshold value as a result ofmonitoring, then the power receiving control unit 292 transmits a powercontrol message to the wireless power transmitter 100 to transfersuitable power.

FIG. 5 is a block diagram illustrating a wireless power transmitterconfigured to have one or more transmission coils receiving poweraccording to an inductive coupling method that can be employed in theembodiments disclosed herein.

Referring to FIG. 5, the power transmission unit 111 of the wirelesspower transmitter 100 according to the embodiments disclosed herein mayinclude one or more transmitting coils 1111 a-1 to 1111 a-n. The one ormore transmitting coils 1111 a-1 to 1111 a-n may be an array of partlyoverlapping primary coils. An active area may be determined by some ofthe one or more transmitting coils.

The one or more transmitting coils 1111 a-1 to 1111 a-n may be mountedat a lower portion of the interface surface. Furthermore, the powertransmission unit 111 may further include a multiplexer 1113 forestablishing and releasing the connection of some of the one or moretransmitting coils 1111 a-1 to 1111 a-n.

Upon detecting the location of the electronic device 200 placed at anupper portion of the interface surface, the power transmission controlunit 112 may take the detected location of the electronic device 200into consideration to control to the multiplexer 1113, thereby allowingcoils that can be placed in an inductive coupling relation to thereceiving coil 2911 a of the electronic device 200 among the one or moretransmitting coils 1111 a-1 to 1111 a-n to be connected to one another.

For this purpose, the power transmission control unit 112 may acquirethe location information of the electronic device 200. For example, thepower transmission control unit 112 may acquire the location of theelectronic device 200 on the interface surface by the location detectionunit (not shown) provided in the wireless power transmitter 100. Foranother example, the power transmission control unit 112 mayalternatively receive a power control message indicating a strength ofthe wireless power signal from an object on the interface surface or apower control message indicating the identification information of theobject using the one or more transmitting coils 1111 a-1 to 1111 a-n,respectively, and determines whether it is located adjacent to which oneof the one or more transmitting coils based on the received result,thereby acquiring the location information of the electronic device 200.

On the other hand, the active area as part of the interface surface maydenote a portion through which a magnetic field with a high efficiencycan pass when the wireless power transmitter 100 transfers power to theelectronic device 200 in a wireless manner. At this time, a singletransmitting coil or one or a combination of more transmitting coilsforming a magnetic field passing through the active area may bedesignated as a primary cell. Accordingly, the power transmissioncontrol unit 112 may determine an active area based on the detectedlocation of the electronic device 200, and establish the connection of aprimary cell corresponding to the active area to control the multiplexer1113, thereby allowing the receiving coil 2911 a of the electronicdevice 200 and the coils belonging to the primary cell to be placed inan inductive coupling relation.

In the meantime, upon disposing one or more electronic devices 200 on aninterface surface of the wireless power transmitter 100, which includesthe one or more transmitting coils 1111 a-1 to 1111 a-n, the powertransmission control unit 112 may control the multiplexer 1113 to allowthe coils belonging to the primary cell corresponding to the position ofeach electronic device to be placed in the inductive coupling relation.Accordingly, the wireless power transmitter 100 may generate thewireless power signal using different coils, thereby transferring it tothe one or more electronic devices in a wireless manner.

Also, the power transmission control unit 112 may set power having adifferent characteristic to be supplied to each of the coilscorresponding to the electronic devices. Here, the wireless powertransmitter 100 may transfer power by differently setting a powertransfer scheme, efficiency, characteristic and the like for eachelectronic device. The power transmission for one or more electronicdevices will be described later with reference to FIG. 8.

On the other hand, the power transmission unit 111 may further includean impedance matching unit (not shown) for controlling an impedance toform a resonant circuit with the coils connected thereto.

Hereinafter, a method for allowing a wireless power transmitter totransfer power according to a resonance coupling method will bedisclosed with reference to FIGS. 6 through 8.

FIG. 6 is a view illustrating a concept in which power is transferred toan electronic device from a wireless power transmitter in a wirelessmanner according to a resonance coupling method.

First, resonance will be described in brief as follows. Resonance refersto a phenomenon in which an amplitude of vibration is remarkablyincreased when periodically receiving an external force having the samefrequency as the natural frequency of a vibration system. Resonance is aphenomenon occurring at all kinds of vibrations such as mechanicalvibration, electric vibration, and the like. Generally, when exerting avibratory force to a vibration system from the outside, if the naturalfrequency thereof is the same as a frequency of the externally appliedforce, then the vibration becomes strong, thus increasing the width.

With the same principle, when a plurality of vibrating bodies separatedfrom one another within a predetermined distance vibrate at the samefrequency, the plurality of vibrating bodies resonate with one another,and in this case, resulting in a reduced resistance between theplurality of vibrating bodies. In an electrical circuit, a resonantcircuit can be made by using an inductor and a capacitor.

When the wireless power transmitter 100 transfers power according to theinductive coupling method, a magnetic field having a specific vibrationfrequency is formed by alternating current power in the powertransmission unit 110. If a resonance phenomenon occurs in theelectronic device 200 by the formed magnetic field, then power isgenerated by the resonance phenomenon in the electronic device 200.

Describing a principle of the resonance coupling, in general, a methodfor transferring power by generating an electromagnetic wave exhibitslow power transmission efficiency.

However, if the plurality of vibrating bodies resonate with each otherin an electromagnetic manner as aforementioned, extremely high powertransmission efficiency may be exhibited due to non affection byadjacent objects except for the vibrating bodies. An energy tunnel maybe generated between the plurality of vibrating bodies which resonatewith each other in the electromagnetic manner. This may be referred toas energy coupling or energy tail.

The resonance coupling disclosed herein may use an electromagnetic wavehaving a low frequency. When power is transferred using theelectromagnetic wave having the low frequency, only a magnetic field mayaffect an area located within a single wavelength of the electromagneticwave. This may be referred to as magnetic coupling or magneticresonance. The magnetic resonance may be generated when the wirelesspower transmitter 100 and the electronic device 200 are located withinthe single wavelength of the electromagnetic wave having the lowfrequency.

Also, as the energy tail is generated in response to the resonancephenomenon, the form of power transmission may exhibit a non-radiativeproperty. Consequently, upon transferring power using suchelectromagnetic wave, a radiative problem which occurs frequently may besolved.

The resonance coupling method may be a method for transferring powerusing the electromagnetic wave with the low frequency, asaforementioned. Thus, the transmitting coil 1111 b of the wireless powertransmitter 100 may form a magnetic field or electromagnetic wave fortransferring power in principle. However, the resonance coupling methodwill be described hereinafter from the perspective of a magneticresonance, namely, a power transmission by a magnetic field.

The resonant frequency may be determined by the following formula inEquation 1.

$\begin{matrix}{f = \frac{1}{2\; \pi \sqrt{LC}}} & \left\lbrack {{Equation}\mspace{14mu} 1} \right\rbrack\end{matrix}$

Here, the resonant frequency (f) is determined by an inductance (L) anda capacitance (C) in a circuit. In a circuit forming a magnetic fieldusing a coil, the inductance can be determined by a number of turns ofthe coil, and the like, and is the capacitance can be determined by agap between the coils, an area, and the like. In addition to the coil, acapacitive resonant circuit may be configured to be connected thereto todetermine the resonant frequency.

Referring to FIG. 6, when power is transmitted in a wireless manneraccording to the resonance coupling method, the power transmission unit111 of the wireless power transmitter 100 may include a transmitting(Tx) coil 1111 b in which a magnetic field is formed and a resonantcircuit (or RESONANT GENERATION CIRCUIT) 1116 connected to thetransmitting coil 1111 b to determine a specific vibration frequency.The resonant circuit 1116 may be implemented by using a capacitivecircuit (capacitors), and the specific vibration frequency may bedetermined based on an inductance of the transmitting coil 1111 b and acapacitance of the resonant circuit 1116.

The configuration of a circuit element of the resonant circuit 1116 maybe implemented in various forms such that the power transmission unit111 forms a magnetic field, and is not limited to a form of beingconnected in parallel to the transmitting coil 1111 b as illustrated inFIG. 6.

Furthermore, the power receiving unit 291 of the electronic device 200may include a resonant circuit 2912 and a receiving (Rx) coil 2911 b togenerate a resonance phenomenon by a magnetic field formed in thewireless power to transmitter 100. In other words, the resonant circuit2912 may be also implemented by using a capacitive circuit, and theresonant circuit 2912 is configured such that a resonant frequencydetermined based on an inductance of the receiving coil 2911 b and acapacitance of the resonant circuit 2912 has the same frequency as aresonant frequency of the formed magnetic field.

The configuration of a circuit element of the resonant circuit 2912 maybe implemented in various forms such that the power receiving unit 291generates resonance by a magnetic field, and is not limited to a form ofbeing connected in series to the receiving coil 2911 b as illustrated inFIG. 6.

The specific vibration frequency in the wireless power transmitter 100may have L_(TX), C_(TX), and may be acquired by using the Equation 1.Here, the electronic device 200 generates resonance when a result ofsubstituting the L_(RX) and C_(RX) of the electronic device 200 to theEquation 1 is same as the specific vibration frequency.

According to a contactless power transfer method by resonance coupling,when the wireless power transmitter 100 and electronic device 200resonate at the same frequency, respectively, an electromagnetic wave ispropagated through a short-range magnetic field, and thus there existsno energy transfer between the devices if they have differentfrequencies.

As a result, an efficiency of contactless power transfer by theresonance coupling method is greatly affected by a frequencycharacteristic, whereas the effect of an alignment and distance betweenthe wireless power transmitter 100 and the electronic device 200including each coil is relatively smaller than the inductive couplingmethod.

Hereinafter, the configuration of a wireless power transmitter and anelectronic device in the resonance coupling method applicable to theembodiments disclosed herein will be described in detail.

FIG. 7A and FIG. 7B are block diagrams illustrating part of the wirelesspower transmitter 100 and the electronic device 200 in a resonancemethod that can be employed in the embodiments disclosed herein.

A configuration of the power transmission unit 110 included in thewireless power transmitter 100 will be described with reference to FIG.7A.

The power transmission unit 111 of the wireless power transmitter 100may include a transmitting (Tx) coil 1111 b, an inverter 1112, and aresonant circuit 1116. The inverter 1112 may be configured to beconnected to the transmitting coil 1111 b and the resonant circuit 1116.

The transmitting coil 1111 b may be mounted separately from thetransmitting coil 1111 a for transferring power according to theinductive coupling method, but may transfer power in the inductivecoupling method and resonance coupling method using one single coil.

The transmitting coil 1111 b, as described above, forms a magnetic fieldfor transferring power. The transmitting coil 1111 b and the resonantcircuit 1116 generate resonance when alternating current power isapplied thereto, and at this time, a vibration frequency may bedetermined based on an inductance of the transmitting coil 1111 b and acapacitance of the resonant circuit 1116.

For this purpose, the inverter 1112 transforms a DC input obtained fromthe power supply unit 190 into an AC waveform, and the transformed ACcurrent is applied to the transmitting coil 1111 b and the resonantcircuit 1116.

In addition, the power transmission unit 111 may further include afrequency adjustment unit 1117 for changing a resonant frequency of thepower to transmission unit 111. The resonant frequency of the powertransmission unit 111 is determined based on an inductance and/orcapacitance within a circuit constituting the power transmission unit111 by Equation 1, and thus the power transmission control unit 112 maydetermine the resonant frequency of the power transmission unit 111 bycontrolling the frequency adjustment unit 1117 to change is theinductance and/or capacitance.

According to some embodiments, the frequency adjustment unit 1117, forexample, may be configured to include a motor for adjusting a distancebetween capacitors included in the resonant circuit 1116 to change acapacitance, or include a motor for adjusting a number of turns ordiameter of the transmitting coil 1111 b to change an inductance, orinclude active elements for determining the capacitance and/orinductance

On the other hand, the power transmission unit 111 may further include apower sensing unit 1115. The operation of the power sensing unit 1115 isthe same as the foregoing description.

Referring to FIG. 7B, a configuration of the power supply unit 290included in the electronic device 200 will be described. The powersupply unit 290, as described above, may include a receiving (Rx) coil2911 b and a resonant circuit 2912.

Moreover, the power receiving unit 291 of the power supply unit 290 mayfurther include a rectifier generation circuit 2913 for converting an ACcurrent generated by resonance phenomenon into DC. The rectifier circuit2913 may be configured similarly to the foregoing description.

In addition, the power receiving unit 291 may further include afrequency adjustment unit 2917 for changing a resonant frequency of thepower receiving unit 291. The resonant frequency of the power receivingunit 291 is determined based on an inductance and/or capacitance withina circuit constituting the power receiving unit 291 by Equation 1, andthus the power receiving control unit 112 may determine the resonantfrequency of the power receiving unit 291 by controlling the frequencyadjustment unit 2917 to change the inductance and/or capacitance.

According to some embodiments, the frequency adjustment unit 2917, forexample, may be configured to include a motor for adjusting a distancebetween capacitors included in the resonant circuit 1116 to change acapacitance. Otherwise, according to some embodiments, the frequencyadjustment unit 2917 include a motor for adjusting a number of turns ora diameter of the transmitting coil 1111 b to change an inductance, orinclude active elements for determining the capacitance and/orinductance.

Furthermore, the power receiving unit 291 may further include a powersensing unit 2914 for monitoring a voltage and/or current of therectified power. The power sensing unit 2914 may be configured similarlyto the foregoing description.

FIG. 8 is a block diagram illustrating a wireless power transmitterconfigured to have one or more transmission coils receiving poweraccording to a resonance coupling method that can be employed in theembodiments disclosed herein.

Referring to FIG. 8, the power transmission unit 111 of the wirelesspower transmitter 100 according to the embodiments disclosed herein mayinclude one or more transmitting coils 1111 b-1 to 1111 b-n and resonantcircuits 1116-1 to 1116-n connected to each transmitting coils.Furthermore, the power transmission unit 111 may further include amultiplexer 1113 for establishing and releasing the connection of someof the one or more transmitting coils 1111 b-1 to 1111 b-n.

The one or more transmitting coils 1111 b-1 to 1111 b-n may beconfigured to have the same vibration frequency, or some of them may beconfigured to have different vibration frequencies. It is determined byan inductance and/or is capacitance of the resonant circuits 1116-1 to1116-n connected to the one or more transmitting coils 1111 b-1 to 1111b-n, respectively.

In the meantime, when one or more electronic devices 200 are disposed inan active area or a detection area of the wireless power transmitter 100including the one or more transmitting coils 1111 b-1 to 1111 b-n, thepower transmission control unit 112 may control the multiplexer 1113 toallow the electronic devices to be placed in different resonancecoupling relations. Accordingly, the wireless power transmitter 100 maywirelessly transfer power to the one or more electronic devices bygenerating the wireless power signal using different coils.

In addition, the power transmission control unit 112 may set power witha different characteristic to be supplied to each of the coilscorresponding to the electronic devices. Here, the wireless powertransmitter 100 may transfer power by differently setting a powertransmission scheme, a resonant frequency, efficiency, a characteristicand the like for each electronic device. The power transmission for oneor more electronic devices will be described later with reference toFIG. 28.

For this purpose, the frequency adjustment unit 1117 may be configuredto change an inductance and/or capacitance of the resonant circuits1116-1 to 1116-n connected to the one or more transmitting coils 1111b-1 to 1111 b-n, respectively. Hereinafter, an example of the wirelesspower transmitter implemented in the form of a wireless charger will bedescribed.

FIG. 9 is a block diagram illustrating a wireless power transmitterfurther including an additional element in addition to the configurationillustrated in FIG. 2A.

Referring to FIG. 9, the wireless power transmitter 100 may furtherinclude a sensor unit 120, a communication unit 130, an output unit 140,a memory 150, and a control unit (or Controller) 180 in addition to thepower transmission unit 110 and power supply unit 190 for supporting atleast one of the foregoing inductive coupling method and resonancecoupling method.

The controller 180 controls the power transmission unit 110, the sensorunit 120, the communication unit 130, the output unit 140, the memory150, and the power supply unit 190.

The controller 180 may be implemented by a module separated from thepower transmission control unit 112 in the power transmission unit 110described with reference to FIG. 2 or may be implemented by a singlemodule.

The sensor unit 120 may include a sensor for detecting the location ofthe electronic device 200. The location information detected by thesensor unit 120 may be used for allowing the power transmission unit 110to transfer power in an efficient manner.

For instance, in case of wireless power transfer according to theinductive coupling method, the sensor unit 120 may be operated as adetection unit, and the location information detected by the sensor unit120 may be used to move or rotate the transmitting coil 1111 a in thepower transmission unit 110.

Furthermore, for example, the wireless power transmitter 100 configuredto include the foregoing one or more transmitting coils may determinecoils that can be placed in an inductive coupling relation or resonancecoupling relation to the receiving coil of the electronic device 200among the one or more transmitting coils based on the locationinformation of the electronic device 200.

On the other hand, the sensor unit 120 may be configured to monitorwhether or not the electronic device 200 approaches a chargeable region.The approach or non-approach detection function of the sensor unit 120may be carried out separately from the function of allowing the powertransmission control unit 112 in the power transmission unit 110 todetect the approach or non-approach of the electronic device 200.

The communication unit 130 performs wired or wireless data communicationwith the electronic device 200. The communication unit 130 may includean electronic component for at least any one of Bluetooth™, Zigbee,Ultra Wide Band (UWB), Wireless USB, Near Field Communication (NFC), andWireless LAN.

The output unit 140 may include at least one of a display unit 141 andan audio output unit (or SOUND OUTPUT UNIT) 142. The display unit 141may include at least one of a liquid crystal display (LCD), a thin filmtransistor-liquid crystal display (TFT-LCD), an organic light-emittingdiode (OLED), a flexible display, and a three-dimensional (3D) display.The display unit 141 may display a charging state under the control ofthe controller 180.

The memory 150 may include at least one storage medium of a flash memorytype, a hard disk type, a multimedia card micro type, a card type memory(e.g., SD or XD memory), a random access memory (RAM), a static randomaccess memory (SRAM), a read-only memory (ROM), an electrically erasableprogrammable read-only memory (EEPROM), a programmable read-only memory(PROM), a magnetic memory, a magnetic disk, an optical disk, and thelike. The wireless power transmitter 100 may operate in association witha web storage performing the storage function of the memory 150 on theInternet. A program or commands performing the foregoing functions ofthe wireless power transmitter 100 may be stored in the memory 150. Thecontrol unit (or Controller) 180 may perform the program or commandsstored in the memory 150 to transmit power in a wireless manner. Amemory controller (not shown) may be used to allow other constituentelements (e.g., controller 180) included in the wireless powertransmitter 100 to access the memory 150.

However, it would be easily understood by those skilled in the art thatthe configuration of a wireless power transmitter according to theembodiment disclosed herein may be applicable to an apparatus, such as adocking station, a terminal cradle device, and an electronic device, andthe like, excluding a case where it is applicable to only a wirelesscharger.

FIG. 10 is view illustrating a configuration in case where an electronicdevice 200 according to the embodiments disclosed herein is implementedin the form of a mobile terminal.

The mobile communication terminal 200 may include a power supply unit290 illustrated in FIG. 2, 4, or 7.

Furthermore, the terminal 200 may further include a wirelesscommunication unit 210, an AudioNideo (A/V) input unit 220, a user inputunit 230, a sensing unit 240, an output unit 250, a memory 260, aninterface unit 270, and a controller 280. FIG. 10 illustrates theterminal 100 having various components, but it is understood thatimplementing all of the illustrated components is not a requirement.Greater or fewer components may alternatively be implemented.

Hereinafter, each component is described in sequence.

The wireless communication unit 210 may typically include one or moremodules which permit wireless communications between the terminal 200and a wireless communication system or between the terminal 200 and anetwork within is which the terminal 200 is located. For example, thewireless communication unit 210 may include a broadcast receiving module211, a mobile communication module 212, a wireless internet module 213,a short-range communication module 214, a position location module 215and the like.

The broadcast receiving module 211 receives a broadcast signal and/orbroadcast associated information from an external broadcast managingentity via a broadcast channel.

The broadcast channel may include a satellite channel and a terrestrialchannel. The broadcast center may indicate a server which generates andtransmits a broadcast signal and/or broadcast associated information ora server which receives a pre-generated broadcast signal and/orbroadcast associated information and sends them to the portableterminal. The broadcast signal may be implemented as a TV broadcastsignal, a radio broadcast signal, and a data broadcast signal, amongothers. The broadcast signal may further include a data broadcast signalcombined with a TV or radio broadcast signal.

Examples of broadcast associated information may denote informationassociated with a broadcast channel, a broadcast program, a broadcastservice provider, and the like. The broadcast associated information maybe provided via a mobile communication network. In this case, it may bereceived by the mobile communication module 212.

The broadcast associated information may be implemented in variousformats. For instance, broadcast associated information may includeElectronic Program Guide (EPG) of Digital Multimedia Broadcasting (DMB),Electronic Service Guide (ESG) of Digital Video Broadcast-Handheld(DVB-H), and the like.

The broadcast receiving module 211 may be configured to receive digitalbroadcast signals transmitted from various types of broadcast systems.Such broadcast systems may include Digital MultimediaBroadcasting-Terrestrial (DMB-T), Digital MultimediaBroadcasting-Satellite (DMB-S), Media Forward Link Only (MediaFLO),Digital Video Broadcast-Handheld (DVB-H), Integrated Services DigitalBroadcast-Terrestrial (ISDB-T) and the like. The broadcast receivingmodule 211 may be configured to be suitable for every broadcast systemtransmitting broadcast signals as well as the digital broadcastingsystems.

Broadcast signals and/or broadcast associated information received viathe broadcast receiving module 211 may be stored in a suitable device,such as a memory 260.

The mobile communication module 212 transmits/receives wireless signalsto/from at least any one of a base station, an external portableterminal, and a server on a mobile communication network. The wirelesssignal may include audio call signal, video (telephony) call signal, orvarious formats of data according to transmission/reception oftext/multimedia messages.

The wireless internet module 213 supports wireless Internet access forthe mobile terminal 200. This module may be internally or externallycoupled to the terminal 100. Examples of such wireless Internet accessmay include Wireless LAN (WLAN) (Wi-Fi), Wireless Broadband (Wibro),Worldwide Interoperability for Microwave Access (Wimax), High SpeedDownlink Packet Access (HSDPA) and the like.

The short-range communication module 214 denotes a module forshort-range communications. Suitable technologies for implementing thismodule may include Bluetooth, Radio Frequency IDentification (RFID),Infrared Data Association (IrDA), Ultra-WideBand (UWB), ZigBee, and thelike. On the other hand, Universal Serial Bus (USB), IEEE 1394,Thunderbolt of Intel technology, and the like, may be used for wiredshort-range communication.

The wireless internet module 213 or the short-range communication module214 may establish data communication connection to the wireless powertransmitter 100.

Through the established data communication, when there is an audiosignal to be outputted while transferring power in a wireless manner,the wireless internet module 213 or the short-range communication module214 may transmit the audio signal to the wireless power transmitter 100through the short-range communication module. Furthermore, through theestablished data communication, when there is information to bedisplayed, the wireless internet module 213 or the short-rangecommunication module 214 may transmit the information to the wirelesspower transmitter 100. Otherwise, the wireless internet module 213 orthe short-range communication module 214 may transmit an audio signalreceived through a microphone integrated in the wireless powertransmitter 100. Furthermore, the wireless internet module 213 or theshort-range communication module 214 may transmit the identificationinformation (e.g., phone number or device name in case of a portablephone) of the mobile terminal 200 to the wireless power transmitter 100through the established data communication.

The position location module 215 is a module for acquiring a position ofthe terminal. An example of the position location module 215 may includea Global Position System (GPS) module.

Referring to FIG. 10, the A/V input unit 220 is configured to provideaudio or video signal input to the portable terminal. The A/V input unit220 may include a camera 221 and a microphone 222. The camera 221processes image frames of still or moving images obtained by an imagesensor in a video call mode or a capture more. The processed imageframes may be displayed on the display unit 251.

The image frames processed by the camera 221 may be stored in the memory260 or transmitted to the exterior via the wireless communication unit210. Two or more cameras 221 may be provided therein according to theuse environment.

The microphone 222 may receive an external audio signal by a microphonein a phone call mode, a recording mode, a voice recognition mode, or thelike to process it into electrical audio data. The processed audio datais converted and outputted into a format transmittable to a mobilecommunication base station via the mobile communication module 212 incase of the phone call mode. The microphone 222 may include variousnoise removal algorithms to remove noises generated while receiving theexternal audio signal.

The user input unit 230 may generate input data to allow the user tocontrol the operation of the terminal. The user input unit 230 mayinclude a keypad, a dome switch, a touchpad (e.g., staticpressure/capacitance), a jog wheel, a jog switch and the like.

The sensing unit 240 may include a proximity sensor 241, a pressuresensor 242, a motion sensor 243, and the like. The proximity sensor 241detects an object approaching the mobile terminal 200, or the presenceor absence of an object existing adjacent to the mobile terminal 200,and the like without any mechanical contact. The proximity sensor 241may detect a proximity object using a change of the AC magnetic field orstatic magnetic field, a change rate of the electrostatic capacity, orthe like. Two or more proximity sensors 241 may be provided according tothe aspect of configuration.

The pressure sensor 242 may detect whether or not a pressure is appliedto the mobile terminal 200, a size of the pressure, and the like. Thepressure sensor 242 may be provided at a portion where the detection ofa pressure is required in the mobile terminal 200 according to the useenvironment. When the pressure sensor 242 is provided in the displayunit 251, it may be possible to identify a touch input through thedisplay unit 251 and a pressure touch input by which a pressure largerthan the touch input is applied according to a signal outputted from thepressure sensor 242. Furthermore, it may be possible to know a size(strength) of the pressure applied to the display unit 251 during theinput of a pressure touch.

The motion sensor 243 detects the location or movement of the mobileterminal 200 using an acceleration sensor, a gyro sensor, and the like.The acceleration sensor used in the motion sensor 243 is an element forconverting an acceleration change in any one direction into anelectrical signal. Two or three axes are typically integrated into apackage to constitute an acceleration sensor, and only one Z-axis may berequired according to the use environment. Accordingly, when anacceleration sensor in the direction of X-axis or Y-axis should be usedinstead of the direction of Z-axis due to any reason, the accelerationsensor may be erected and mounted on a main substrate using a separatepiece substrate. Furthermore, the gyro sensor is a sensor for measuringan angular speed of the mobile terminal 200 in a rotational movement todetect a rotated angle with respect to each reference direction. Forinstance, the gyro sensor may detect each rotational angle, i.e.,azimuth, pitch and roll, with reference to three directional axes.

The output unit 250 is provided to output visual, auditory, or tactileinformation. The output unit 250 may include a display unit 251, anaudio output module 252, an alarm unit 253, a haptic module 254, and thelike.

The display unit 251 may display (output) information processed in theterminal 200. For example, when the terminal is in a phone call mode,the display unit 251 will provide a User Interface (UI) or Graphic UserInterface (GUI) associated with the call. When the terminal is in avideo call mode or a capture mode, the display unit 251 may displayimages captured and/or received, UI, or GUI.

The display unit 251 may include at least one of a liquid crystaldisplay (LCD), a thin film transistor-liquid crystal display (TFT-LCD),an organic light-emitting diode (OLED), a flexible display, athree-dimensional (3D) display, and the like.

Some of those displays may be configured as a transparent type or anlight transmission type through which the outside is visible, which isreferred to as a transparent display. A representative example of thetransparent display may include a Transparent OLED (TOLED), or the like.The rear surface of the display unit 151 may also be implemented to beoptically transparent. Under this configuration, the user can view anobject positioned at a rear side of the terminal body through a regionoccupied by the display unit 251 of the terminal body.

The display unit 251 may be implemented in two or more in numberaccording to a configured aspect of the terminal 200. For instance, aplurality of the display units 251 may be arranged on one surface to bespaced apart from or integrated with each other, or may be arranged ondifferent surfaces.

Here, if the display unit 251 and a touch sensitive sensor (referred toas a is touch sensor) have a layered structure therebetween, the displayunit 251 may be used as an input device rather than an output device.The touch sensor may be implemented as a touch film, a touch sheet, atouch pad, and the like.

The touch sensor may be configured to convert changes of a pressureapplied to a specific part of the display unit 251, or a capacitanceoccurring from a specific part of the display unit 251, into electricinput signals. Also, the touch sensor may be configured to sense notonly a touched position and a touched area, but also touch pressure.

When touch inputs are sensed by the touch sensors, corresponding signalsare sent to a touch controller. The touch controller processes thereceived signals, and then transmits corresponding data to thecontroller 280. Accordingly, the controller 280 may sense which regionof the display unit 151 has been touched.

The proximity sensor 241 may be arranged at an inner region of theterminal covered by the touch screen, or near the touch screen. Theproximity sensor refers to a sensor to sense the presence or absence ofan object approaching a surface to be sensed, or an object disposed neara surface to be sensed, using an electromagnetic field or infrared rayswithout a mechanical contact. The proximity sensor has a longer lifespanand a more enhanced utility than a contact sensor.

The proximity sensor may include a transmissive type photoelectricsensor, a direct reflective type photoelectric sensor, a mirrorreflective type photoelectric sensor, a high-frequency oscillationproximity sensor, a capacitance type proximity sensor, a magnetic typeproximity sensor, an infrared rays proximity sensor, and so on. When thetouch screen is implemented as a capacitance type, proximity of apointer to the touch screen is sensed by changes of an electromagneticfield. In this case, the touch screen (touch sensor) may be categorizedinto a proximity sensor.

Hereinafter, for the sake of brief explanation, a status that thepointer is positioned to be proximate onto the touch screen withoutcontact will be referred to as a “proximity touch”, whereas a statusthat the pointer substantially comes in contact with the touch screenwill be referred to as a “contact touch”. For the position correspondingto the proximity touch of the pointer on the touch screen, such positioncorresponds to a position where the pointer faces perpendicular to thetouch screen upon the proximity touch of the pointer.

The proximity sensor senses proximity touch, and proximity touchpatterns (e.g., distance, direction, speed, time, position, movingstatus, etc.). Information relating to the sensed proximity touch andthe sensed proximity touch patterns may be output onto the touch screen.

The audio output module 252 may output audio data received from thewireless communication unit 210 or stored in the memory 260, in acall-receiving mode, a call-placing mode, a recording mode, a voicerecognition mode, a broadcast reception mode, and so on. The audiooutput module 252 may output audio signals relating to functionsperformed in the terminal 200, e.g., sound alarming a call received or amessage received, and so on. The audio output module 252 may include areceiver, a speaker, a buzzer, and so on.

The alarm 253 outputs signals notifying the occurrence of an event fromthe terminal 200. The event occurring from the terminal 100 may includecall received, message received, key signal input, touch input, and soon. The alarm 253 may output not only video or audio signals, but alsoother types of signals such as signals notifying occurrence of events ina vibration manner. Since the video or audio signals can be outputthrough the display unit 251 or the audio output unit 252, the displayunit 251 and the audio output module 252 may be categorized into part ofthe alarm 253.

The haptic module 254 generates various tactile effects which a user canfeel. A representative example of the tactile effects generated by thehaptic module 254 includes vibration. Vibration generated by the hapticmodule 254 may have a controllable intensity, a controllable pattern,and so on. For instance, different vibration may be output in asynthesized manner or in a sequential manner.

The haptic module 254 may generate various tactile effects, includingnot only vibration, but also arrangement of pins vertically moving withrespect to a skin being contacted, air injection force or air suctionforce through an injection hole or a suction hole, touch by a skinsurface, presence or absence of contact with an electrode, effects bystimulus such as an electrostatic force, reproduction of cold or hotfeeling using a heat absorbing device or a heat emitting device, and thelike.

The haptic module 254 may be configured to transmit tactile effectsthrough the user's direct contact, or the user's muscular sense using afinger or a hand. The haptic module 254 may be implemented in two ormore in number according to the configuration of the terminal 200.

The memory 260 may store a program for the processing and control of thecontroller 280. Alternatively, the memory 260 may temporarily storeinput/output data (e.g., phonebook data, messages, still images, videoand the like). Also, the memory 260 may store data related to variouspatterns of vibrations and audio output upon the touch input on thetouch screen.

In some embodiments, software components including an operating system(not shown), a module performing a wireless communication unit 210function, a module operating together with the user input unit 230, amodule operating together with the A/V input unit 220, a moduleoperating together with the output unit 250 may be stored in the memory260. The operating system (e.g., LINUX, UNIX, OS X, WINDOWS, Chrome,Symbian, iOS, Android, VxWorks, or other embedded operating systems) mayinclude various software components and/or drivers to control systemtasks such as memory management, power management, and the like.

In addition, the memory 260 may store a setup program associated withcontactless power transfer or wireless charging. The setup program maybe implemented by the controller 280.

Furthermore, the memory 260 may store an application associated withcontactless power transfer (or wireless charging) downloaded from anapplication providing server (for example, an app store). The wirelesscharging related application is a program for controlling wirelesscharging transmission, and thus the electronic device 200 may receivepower from the wireless power transmitter 100 in a wireless manner orestablish connection for data communication with the wireless powertransmitter 100 through the relevant program.

The memory 260 may be implemented using any type of suitable storagemedium including a flash memory type, a hard disk type, a multimediacard micro type, a memory card type (e.g., SD or xD memory), a randomaccess memory (RAM), a static random access memory (SRAM), a read-onlymemory (ROM), an electrically erasable programmable read-only memory(EEPROM), a programmable read-only memory (PROM), a magnetic memory, amagnetic disk, an optical disk, and the like. Also, the terminal 200 maybe operated in association with a web storage performing the storagefunction of the memory 160 on the Internet.

The interface unit 270 may generally be implemented to interface theportable terminal with all external devices. The interface unit 270 mayallow a data reception from an external device, a power delivery to eachcomponent in the terminal 200, or a data transmission from the terminal200 to an external device.

The interface unit 270 may include, for example, wired/wireless headsetports, external charger ports, wired/wireless data ports, memory cardports, ports for coupling devices having an identification module, audioinput/output (I/O) ports, video input/output (I/O) ports, earphoneports, and the like.

The identification module may be configured as a chip for storingvarious information required to authenticate an authority to use theterminal 200, which may include a User Identity Module (UIM), aSubscriber Identity Module (SIM), and the like. Also, the device havingthe identification module (hereinafter, referred to as “identificationdevice”) may be implemented in a type of smart card. Hence, theidentification device can be coupled to the terminal 200 via a port.

Also, the interface unit may serve as a path for power to be suppliedfrom an external cradle to the terminal 200 when the terminal 100 isconnected to the external cradle or as a path for transferring variouscommand signals inputted from the cradle by a user to the terminal 200.Such various command signals or power inputted from the cradle mayoperate as signals for recognizing that the terminal 200 has accuratelybeen mounted to the cradle.

The controller 280 typically controls the overall operations of theterminal 200. For example, the controller 280 performs the control andprocessing associated with telephony calls, data communications, videocalls, and the like. The controller 280 may include a multimedia module281 for multimedia playback. The multimedia module 281 may beimplemented within the controller 280, or implemented separately fromthe controller 280. Also, the controller 280 may be implemented into aseparate module from the power receiving control unit 292 within thepower supply unit 290 or a single module.

The controller 280 can perform a pattern recognition processing so as torecognize a writing input or image drawing input carried out on thetouch screen as a text or image.

The controller 280 performs wired or wireless charging according to theuser input or internal input. Here, the internal input represents asignal for notifying that an induced current generated from a secondarycoil within the terminal has been detected.

When the aforementioned wireless charging is carried out, an operationof allowing the controller 280 to control each constituent element willbe described in detail below with reference to the operation phase inFIG. 14. As described above, the power receiving control unit 292 withinthe power supply unit 290 may be implemented to be included in thecontroller 280, and in the present disclosure, it should be understoodthat the controller 280 performs the operation by the power receivingcontrol unit 292.

The power supply unit 290 receives internal and external power under thecontrol of the controller 280 to supply power required for the operationof each constituent element.

The power supply unit 290 is provided with a battery 299 for supplyingpower to each constituent element of the terminal 200, and the battery299 may include a charger 298 for performing wired or wireless charging.

The present illustration discloses a mobile terminal as an example ofthe apparatus for receiving power in a wireless manner. However, theconfiguration according to the embodiment disclosed herein may be alsoapplicable to a stationary terminal, such as a digital TV, a desktopcomputer, and the like.

FIG. 11A and FIG. 11B are view illustratings the concept of transmittingand receiving a packet between a wireless power transmitter and anelectronic device through the modulation and demodulation of a wirelesspower signal in transferring power in a wireless manner disclosedherein.

Referring to FIG. 11A, the wireless power signal formed by the powertransmission unit 111 forms a closed-loop within a magnetic field orelectromagnetic field, and therefore, when the electronic device 200modulates the wireless power signal while receiving the wireless powersignal, the wireless power transmitter 100 may detect the modulatedwireless power signal. The power communications modulation/demodulationunit 113 may demodulate the detected wireless power signal, and decodesthe packet from the modulated wireless power signal.

On the other hand, a modulation method used for communication betweenthe wireless power transmitter 100 and the electronic device 200 may beamplitude modulation. As described above, the amplitude modulationmethod may be a backscatter modulation method in which themodulation/demodulation unit 293 at the side of the electronic device200 changes an amplitude of the wireless power signal 10 a formed by thepower transmission unit 111 and the modulation/demodulation unit 293 atthe side of the wireless power transmitter 100 detects an amplitude ofthe modulated wireless power signal 10 b.

Specifically, further referring to FIG. 11B, the power receiving controlunit 292 at the side of the electronic device 200 modulates the wirelesspower signal 10 a received through the power receiving unit 291 bychanging a load impedance within the modulation/demodulation unit 293.power receiving control unit 292 modulates the wireless power signal 10a to include a packet including a power control message to betransmitted to the wireless power transmitter 100.

Then, the power transmission control unit 112 at the side of thewireless power transmitter 100 demodulates the modulated wireless powersignal 10 b through an envelope detection process, and decodes thedetected signal 10 c into digital data 10 d. The demodulation processdetects a current or voltage flowing into the power transmission unit111 to be classified into two states, a HI phase and a LO phase, andacquires a packet to be transmitted by the electronic device 200 basedon digital data classified according to the states.

Hereinafter, a process of allowing the wireless power transmitter 100 toacquire a power control message to be transmitted by the electronicdevice 200 from the demodulated digital data will be described.

FIG. 12 is a view illustrating a method of showing data bits and byteconstituting a power control message provided by the wireless powertransmitter 100.

Referring to FIG. 12A, the power transmission control unit 112 detectsan encoded bit using a clock signal (CLK) from an envelope detectedsignal. The detected encoded bit is encoded according to a bit encodingmethod used in the modulation process at the side of the electronicdevice 200. The bit encoding method may correspond to any one ofnon-return to zero (NRZ) and bi-phase encoding.

For instance, the detected bit may be a differential bi-phase (DBP)encoded bit. According to the DBP encoding, the power receiving controlunit 292 at the side of the electronic device 200 is allowed to have twostate transitions to encode data bit 1, and to have one state transitionto encode data bit 0. In other words, data bit 1 may be encoded in sucha manner that a transition between the HI state and LO state isgenerated at a rising edge and falling edge of the clock signal, anddata bit 0 may be encoded in such a manner that a transition between theHI state and LO state is generated at a rising edge of the clock signal.

On the other hand, the power transmission control unit 112 may acquiredata in a byte unit using a byte format constituting a packet from a bitstring detected according to the bit encoding method. For instance, thedetected bit string may be transferred by using an 11-bit asynchronousserial format as illustrated in FIG. 12B. In other words, the detectedbit may include a start bit indicating the beginning of a byte and astop bit indicating the end of a byte, and also include data bits (b0 tob7) between the start bit and the stop bit. Furthermore, it may furtherinclude a parity bit for checking an error of data. The data in a byteunit constitutes a packet including a power control message.

FIG. 13 is a view illustrating a packet including a power controlmessage used in a contactless power transfer method according to theembodiments disclosed herein.

The packet 500 may include a preamble 510, a header 520, a message 530,and a checksum 540.

The preamble 510 may be used to perform synchronization with datareceived by the wireless power transmitter 100 and detect the start bitof the header 520. The preamble 510 may be configured to repeat the samebit. For instance, the preamble 510 may be configured such that data bit1 according to the DBP encoding is repeated eleven to twenty five times.

The header 520 may be used to indicate a type of the packet 500. A sizeof the message 530 and the kind thereof may be determined based on avalue indicated by the header 520. The header 520 is a value having apredetermined size to be positioned subsequent to the preamble 510. Forinstance, the header 520 may be a byte in size.

The message 530 may be configured to include data determined based onthe header 520. The message 530 has a predetermined size according tothe kind thereof.

The checksum 540 may be used to detect an error that can be occurred inthe header 520 and the message 530 while transmitting a power controlmessage. The header 520 and the message 530 excluding the preamble 510for synchronization and the checksum 540 for error checking may bereferred to as command-packet.

Hereinafter, description will be given of operation phases of thewireless power transmitter 100 and the electronic device 200.

FIG. 14 illustrates the operation phases of the wireless powertransmitter 100 and electronic device 200 according to the embodimentsdisclosed herein. Furthermore, FIGS. 15 through 20 illustrates thestructure of packets including a power control message between thewireless power transmitter 100 and electronic device 200.

Referring to FIG. 14, the operation phases of the wireless powertransmitter 100 and the electronic device 200 for wireless powertransfer may be divided into a selection phase (state) 610, a ping phase620, an identification and configuration phase 630, and a power transferphase 640.

The wireless power transmitter 100 detects whether or not objects existwithin a range that the wireless power transmitter 100 can transmitpower in a wireless manner in the selection phase 610, and the wirelesspower transmitter 100 sends a detection signal to the detected objectand the electronic device 200 sends a response to the detection signalin the ping phase 620.

Furthermore, the wireless power transmitter 100 identifies theelectronic device 200 selected through the previous phases and acquiresconfiguration information for power transmission in the identificationand configuration phase 630. The wireless power transmitter 100transmits power to the electronic device 200 while controlling powertransmitted in response to a control message received from theelectronic device 200 in the power transfer phase 640.

Hereinafter, each of the operation phases will be described in detail.

1) Selection Phase

The wireless power transmitter 100 in the selection phase 610 performs adetection process to select the electronic device 200 existing within adetection area. The detection area, as described above, refers to aregion in which an object within the relevant area can affect on thecharacteristic of the power of the power transmission unit 111. Comparedto the ping phase 620, the detection process for selecting theelectronic device 200 in the selection phase 610 is a process ofdetecting a change of the power amount for forming a wireless powersignal in the power transmission unit at the side of the wireless powertransmitter 100 to check whether any object exists within apredetermined range, instead of the scheme of receiving a response fromthe electronic device 200 using a power control message. The detectionprocess in the selection phase 610 may be referred to as an analog pingprocess in the aspect of detecting an object using a wireless powersignal without using a packet in a digital format in the ping phase 620which will be described later.

The wireless power transmitter 100 in the selection phase 610 can detectthat an object comes in or out within the detection area. Furthermore,the wireless power transmitter 100 can distinguish the electronic device200 capable of transferring power in a wireless manner from otherobjects (for example, a key, a coin, etc.) among objects located withinthe detection area.

As described above, a distance that can transmit power in a wirelessmanner may be different according to the inductive coupling method andresonance coupling method, and thus the detection area for detecting anobject in the selection phase 610 may be different from one another.

First, in case where power is transmitted according to the inductivecoupling method, the wireless power transmitter 100 in the selectionphase 610 can monitor an interface surface (not shown) to detect thealignment and removal of objects.

Furthermore, the wireless power transmitter 100 may detect the locationof the electronic device 200 placed on an upper portion of the interfacesurface. As described above, the wireless power transmitter 100 formedto include one or more transmitting coils may perform the process ofentering the ping phase 620 in the selection phase 610, and checkingwhether or not a response to the detection signal is transmitted fromthe object using each coil in the ping phase 620 or subsequentlyentering the identification phase 630 to check whether identificationinformation is transmitted from the object. The wireless powertransmitter 100 may determine a coil to be used for contactless powertransfer based on the detected location of the electronic device 200acquired through the foregoing process.

Furthermore, when power is transmitted according to the resonancecoupling method, the wireless power transmitter 100 in the selectionphase 610 can detect an object by detecting that any one of a frequency,a current and a voltage of the power transmission unit is changed due toan object located within the detection area.

On the other hand, the wireless power transmitter 100 in the selectionphase 610 may detect an object by at least any one of the detectionmethods using the inductive coupling method and resonance couplingmethod. The wireless power transmitter 100 may perform an objectdetection process according to each power transmission method, andsubsequently select a method of detecting the object from the couplingmethods for contactless power transfer to advance to other phases 620,630, 640.

On the other hand, for the wireless power transmitter 100, a wirelesspower signal formed to detect an object in the selection phase 610 and awireless power signal formed to perform digital detection,identification, configuration and power transmission in the subsequentphases 620, 630, 640 may have a different characteristic in thefrequency, strength, and the like. It is because the selection phase 610of the wireless power transmitter 100 corresponds to an idle phase fordetecting an object, thereby allowing the wireless power transmitter 100to reduce consumption power in the idle phase or generate a specializedsignal for effectively detecting an object.

2) Ping Phase

The wireless power transmitter 100 in the ping phase 620 performs aprocess of detecting the electronic device 200 existing within thedetection area through a power control message. Compared to thedetection process of the electronic device 200 using a characteristic ofthe wireless power signal and the like in the selection phase 610, thedetection process in the ping phase 620 may be referred to as a digitalping process.

The wireless power transmitter 100 in the ping phase 620 forms awireless power signal to detect the electronic device 200, modulates thewireless power signal modulated by the electronic device 200, andacquires a power control message in a digital data format correspondingto a response to the detection signal from the modulated wireless powersignal. The wireless power transmitter 100 may receive a power controlmessage corresponding to the response to the detection signal torecognize the electronic device 200 which is a subject of powertransmission.

The detection signal formed to allowing the wireless power transmitter100 in the ping phase 620 to perform a digital detection process may bea wireless power signal formed by applying a power signal at a specificoperating point for a predetermined period of time. The operating pointmay denote a frequency, duty cycle, and amplitude of the voltage appliedto the transmitting (Tx) coil. The wireless power transmitter 100 maygenerate the detection signal generated by applying the power signal ata specific operating point for a predetermined period of time, andattempt to receive a power control message from the electronic device200.

On the other hand, the power control message corresponding to a responseto the detection signal may be a message indicating a strength of thewireless power signal received by the electronic device 200. Forexample, the electronic device 200 may transmit a signal strength packet5100 including a message indicating the received strength of thewireless power signal as a is response to the detection signal asillustrated in FIG. 15. The packet 5100 may include a header 5120 fornotifying a packet indicating the signal strength and a message 5130indicating a strength of the power signal received by the electronicdevice 200. The strength of the power signal within the message 5130 maybe a value indicating a degree of inductive coupling or resonancecoupling for power transmission between the wireless power transmitter100 and the electronic device 200.

The wireless power transmitter 100 may receive a response message to thedetection signal to find the electronic device 200, and then extend thedigital detection process to enter the identification and configurationphase 630. In other words, the wireless power transmitter 100 maintainsthe power signal at a specific operating point subsequent to finding theelectronic device 200 to receive a power control message required in theidentification and configuration phase 630.

However, if the wireless power transmitter 100 is not able to find theelectronic device 200 to which power can be transferred, then theoperation phase of the wireless power transmitter 100 will be returnedto the selection phase 610.

3) Identification and Configuration Phase

The wireless power transmitter 100 in the identification andconfiguration phase 630 may receive identification information and/orconfiguration information transmitted by the electronic device 200,thereby controlling power transmission to be effectively carried out.

The electronic device 200 in the identification and configuration phase630 may transmit a power control message including its ownidentification information. For this purpose, the electronic device 200,for instance, may transmit an identification packet 5200 including amessage indicating the identification information of the electronicdevice 200 as illustrated in FIG. 16A. The packet 5200 may include aheader 5220 for notifying a packet indicating identification informationand a message 5230 including the identification information of theelectronic device. The message 5230 may include information (2531 and5232) indicating a version of the contract for contactless powertransfer, information 5233 for identifying a manufacturer of theelectronic device 200, information 5234 indicating the presence orabsence of an extended device identifier, and a basic device identifier5235. Furthermore, if it is displayed that an extended device identifierexists in the information 5234 indicating the presence or absence of anextended device identifier, then an extended identification packet 5300including the extended device identifier as illustrated in FIG. 16B willbe transmitted in a separate manner. The packet 5300 may include aheader 5320 for notifying a packet indicating an extended deviceidentifier and a message 5330 including the extended device identifier.When the extended device identifier is used as described above,information based on the manufacturer's identification information 5233,the basic device identifier 5235 and the extended device identifier 5330will be used to identify the electronic device 200.

The electronic device 200 may transmit a power control message includinginformation on expected maximum power in the identification andconfiguration phase 630. To this end, the electronic device 200, forinstance, may transmit a configuration packet 5400 as illustrated inFIG. 17. The packet may include a header 5420 for notifying that it is aconfiguration packet and a message 5430 including information on theexpected maximum power. The message 5430 may include power class 5431,information 5432 on expected maximum power, an indicator 5433 indicatinga method of determining a current of a main cell at the side of thewireless power transmitter, and the number 5434 of optionalconfiguration packets. The indicator 5433 may indicate whether or not acurrent of the main cell at the side of the wireless power transmitteris determined as specified in the contract for wireless power transfer.

Meanwhile, the electronic device 200 according to the exemplaryembodiments may transmit a power control message, which includesrequired power information thereof and associated profile information,to the wireless power transmitter 100. In some exemplary embodiments,the required power information related to the electronic device 200 orthe profile information may be transmitted by being included in theconfiguration packet 5400 as illustrated in FIG. 17. Alternatively, therequired power information related to the electronic device 200 or theprofile information may be transmitted by being included in a separatepacket for configuration.

On the other hand, the wireless power transmitter 100 may generate apower transfer contract which is used for power charging with theelectronic device 200 based on the identification information and/orconfiguration information. The power transfer contract may include thelimits of parameters determining a power transfer characteristic in thepower transfer phase 640.

The wireless power transmitter 100 may terminate the identification andconfiguration phase 630 and return to the selection phase 610 prior toentering the power transfer phase 640. For instance, the wireless powertransmitter 100 may terminate the identification and configuration phase630 to find another electronic device that can receive power in awireless manner.

4) Power Transfer Phase

The wireless power transmitter 100 in the power transfer phase 640transmits power to the electronic device 200.

The wireless power transmitter 100 may receive a power control messagefrom the electronic device 200 while transferring power, and control acharacteristic of the power applied to the transmitting coil in responseto the received power control message. For example, the power controlmessage used to control a characteristic of the power applied to thetransmitting coil may be included in a control error packet 5500 asillustrated in FIG. 18. The packet 5500 may include a header 5520 fornotifying that it is a control error packet and a message 5530 includinga control error value. The wireless power transmitter 100 may controlthe power applied to the transmitting coil according to the controlerror value. In other words, a current applied to the transmitting coilmay be controlled so as to be maintained if the control error value is“0”, reduced if the control error value is a negative value, andincreased if the control error value is a positive value.

The wireless power transmitter 100 may monitor parameters within a powertransfer contract generated based on the identification informationand/or configuration information in the power transfer phase 640. As aresult of monitoring the parameters, if power transmission to theelectronic device 200 violates the limits included in the power transfercontract, then the wireless power transmitter 100 may cancel the powertransmission and return to the selection phase 610.

The wireless power transmitter 100 may terminate the power transferphase 640 based on a power control message transferred from theelectronic device 200.

According to some embodiments, if the charging of a battery has beencompleted while charging the battery using power transferred by theelectronic device 200, then a power control message for requesting thesuspension of wireless power transfer will be transferred to thewireless power transmitter 100. In this case, the wireless powertransmitter 100 may receive a message for requesting the suspension ofthe power transmission, and then terminate wireless power transfer, andreturn to the selection phase 610.

Furthermore, according to some embodiments, the electronic device 200may transfer a power control message for requesting renegotiation orreconfiguration to update the previously generated power transfercontract. The electronic device 200 may transfer a message forrequesting the renegotiation of the power transfer contract when it isrequired a larger or smaller amount of power than the currentlytransmitted power amount. In this case, the wireless power transmitter100 may receive a message for requesting the renegotiation of the powertransfer contract, and then terminate contactless power transfer, andreturn to the identification and configuration phase 630.

To this end, a message transmitted by the electronic device 200, forinstance, may be an end power transfer packet 5600 as illustrated inFIG. 19. The packet 5600 may include a header 5620 for notifying that itis an end power transfer packet and a message 5630 including an endpower transfer code indicating the cause of the suspension. The endpower transfer code may indicate any one of charge complete, internalfault, over temperature, over voltage, over current, battery failure,reconfigure, no response, and unknown error.

As described above, the electronic device may be a stationary terminalsuch as a digital TV, a desktop computer, a kitchen appliance and thelike. In particular, when power is supplied to a digital TV in awireless manner, it may be possible to implement a wireless TV. Here,the wireless TV denotes a television with no cable for supplying power.In this case, power consumption may occur due to standby power in thewireless TV, but according to the present disclosure, there is proposeda wireless charging scheme capable of reducing the standby power.

Hereinafter, a wireless power transmitter and a method thereof capableof reducing the standby power of a wireless power transmitter and anelectronic device 200 when the electronic device 200 to which a wirelesspower receiver is applied is turned off will be described with referenceto FIGS. 20 and 21.

FIG. 20 is a configuration diagram illustrating a wireless powertransmitter for reducing standby power according to an embodiment of thepresent disclosure.

As illustrated in FIG. 20, the wireless power transmitter 100 forreducing standby power according to an embodiment of the presentdisclosure may be configured to receive a power-on signal when thepower-on signal is generated from a remote controller and then transferpower to a wireless charging coil of an electronic device which is awireless power receiver. Through this, the electronic device may beturned on, thereby preventing the consumption of standby power in theelectronic device.

The electronic device may be a low power product such as a mobileterminal, for example, but according to the following illustration, itmay be also a home appliance product (digital TV, microwave oven,electric range, electronic burner, etc.) required for power aboveseveral tens of watts.

More specifically, the wireless power transmitter 100 may include areceiving unit (remote control signal receiver) 300 configured toreceive a power-on signal or power-off signal from a remote controller301; a power transmission controller 112 configured to generate a drivesignal to supply power for the operation of the electronic device 200when the power-on signal is received at the receiving unit 300; a powersupply unit 190 configured to supply power (for example, DC inputvoltage); and a power transmission unit 111 configured to form awireless power signal based on the supplied DC input voltage and thedrive signal to transmit wireless power to the wireless power receiver(electronic device) 200. The DC input voltage may be converted into analternating current by a switching operation using the drive signal. Thepower transmission controller 112 adjusts a wireless power transmissionrate according to the usage of the electronic device 200.

The power transmission unit 111 of the wireless power transmitter 100may include a transmitting (Tx) coil 1111 b, an inverter 1112, and aresonant circuit 1116. The inverter 1112 may be configured to beconnected to the transmitting coil 1111 b and the resonant circuit 1116.

The transmitting coil 1111 b may be mounted separately from thetransmitting coil 1111 a for transferring power according to theinductive coupling method, but may transfer power in the inductivecoupling method and resonance coupling method using one single coil.

The transmitting coil 1111 b, as described above, forms a magnetic fieldfor transferring power. The transmitting coil 1111 b and the resonantcircuit 1116 generate resonance when alternating current power isapplied thereto, and at this time, a vibration frequency may bedetermined based on an inductance of the transmitting coil 1111 b and acapacitance of the resonant circuit 1116.

For this purpose, the inverter 1112 transforms a DC input obtained fromthe power supply unit 190 into an AC waveform, and the transformed ACcurrent is applied to the transmitting coil 1111 b and the resonantcircuit 1116. In addition, the power transmission unit 111 may furtherinclude a frequency adjustment unit 1117 for changing a resonantfrequency of the power transmission unit 111. The resonant frequency ofthe power transmission unit 111 is determined based on an inductanceand/or capacitance within a circuit constituting the power transmissionunit 111 by Equation 1, and thus the power transmission control unit 112may determine the resonant frequency of the power transmission unit 111by controlling the frequency adjustment unit 1117 to change theinductance and/or capacitance.

According to some embodiments, the frequency adjustment unit 1117 may beconfigured to include a motor for adjusting a distance betweencapacitors included in the resonant circuit 1116 to change acapacitance. Furthermore, according to some embodiments, the frequencyadjustment unit 1117 may include a motor for adjusting a number of turnsor diameter of the transmitting coil 1111 b to change an inductance.According to some embodiments, the frequency adjustment unit 1117 mayinclude active elements for determining the capacitance and/orinductance

The power transmission unit 111 may further include a power sensing unit1115. The operation of the power sensing unit 1115 is the same as theforegoing description.

The wireless power transmitter 100 may further include amodulation/demodulation unit 113 electrically connected to the powertransmission unit 111. The modulation/demodulation unit 113 may modulatea wireless power signal that has been modulated by the electronic device200 and use it to receive the power control message.

FIG. 21 is a flow chart illustrating a wireless power transmissionmethod for reducing standby power according to an embodiment of thepresent disclosure.

First, the receiving unit (remote control signal receiver) 300 receivesa power-on or power-off signal from the remote controller 301. Uponreceiving the power-off signal, the receiving unit 300 turns off thepower transmission controller 112, thereby turning off the wirelesspower transmitter 100 excluding the receiving unit 300 while at the sametime blocking wireless power transmitted from the wireless powertransmitter 100 to the wireless power receiver (electronic device) 200(S11).

The receiving unit 300 may receive power from an independently separatedpower supply source (for example, battery, DC supply terminal, etc.).For example, the receiving unit 300 may include a charging device (notshown) configured to charge the wireless power output from the wirelesspower receiver (electronic device) 200, and supply the charged power tothe receiving unit 300 for a period of time in which the wireless powertransmitter 100 and/or the wireless power receiver (electronic device)200 is turned off. The charging device may be a rechargeable battery, asupercapacitor, or the like.

When a power-on signal is received from the remote controller 301 (S12),the receiving unit 300 turns on the wireless power transmitter 100excluding the receiving unit 300 based on the power-on signal (S13). Forexample, when the power-on signal is received from the remote controller301 (S12), the receiving unit 300 turns on the power transmissioncontroller 112 of the wireless power transmitter 100 based on thepower-on signal to operate the wireless power transmitter 100. Here, thepower supply unit 190 supplies a DC input voltage to the powertransmission controller 112 when the power transmission controller 112is turned on.

When the power-on signal is received at the receiving unit 300, thepower transmission controller 112 generates a drive signal to supplypower for the operation of the 200 (S14).

The power transmission unit 111 forms a wireless power signal based onthe supplied DC input voltage and the drive signal (S15) to transmitwireless power to the wireless power receiver (electronic device) 200(S16). The wireless power receiver (electronic device) 200 is operated(turned on) when receiving the wireless power.

Consequently, according to a wireless power transmitter and a methodthereof for reducing standby power according to another embodiment ofthe present disclosure, the receiving unit for receiving a power-on/offsignal may be turned on when the electronic device 200 to which thewireless power receiver is applied may be turned off, thereby reducingthe standby power of the wireless power transmitter and the electronicdevice 200. For example, only the consumption power of the receivingunit 300 of the wireless power transmitter 100 may be used when theelectronic device 200 is not used, thereby reducing the standby power ofthe wireless power transmitter 100 and the standby power of theelectronic device 200.

Hereinafter, another wireless power transmitter and a method thereofcapable of reducing the standby power of the wireless power transmitterand the electronic device 200 in a state that the electronic device 200to which the wireless power receiver is applied is turned off will bedescribed with reference to FIGS. 22 through 24.

FIG. 22 is a configuration diagram illustrating a wireless powertransmitter for reducing standby power according to another embodimentof the present disclosure. As illustrated in FIG. 22, the wireless powertransmitter 100 for reducing standby power according to anotherembodiment of the present disclosure is configured to transfer low powerto a remote control receiver circuit of the wireless power receiver(electronic device). When a power-on signal is generated from a remotecontroller, the remote control receiver circuit may receive the signal,and then power on the electronic device, thereby preventing theconsumption of standby power in the electronic device.

In this case, the remote control receiver circuit is driven at lowpower, and accordingly, the wireless power transmitter may include aseparate dedicated block for operating the remote control receivercircuit to transmit the low power, and the electronic device isconfigured to receive the low power and supply it to the remote controlreceiver circuit. When the electronic device which is a load is in apower-off state, a main power transmission block is not operated butonly a dedicated block for operating the remote control receiver circuitis operated, and when a power-on signal is received by a remotecontroller or the like, the operation of the main power transmissionblock is started by communication between the wireless power transmitterand wireless power receiver while at the same time starting theoperation of the electronic device.

For example, the wireless power transmitter 100 may include a powersupply unit (main power supply unit) 190 configured to supply a DC inputvoltage;

a sub-power supply unit 400 configured to convert the DC input voltageto a low voltage, and form a wireless low power signal based on theconverted low voltage and a low power drive signal for the operation ofthe receiving unit 300 to transmit wireless low power, and receive andsupply (apply) the wireless low power;

a receiving unit 300 configured to receive a power-on signal orpower-off signal from the remote controller 301 based on the wirelesslow power supplied from the sub-power supply unit 400;

a power transmission controller 112 configured to generate a drivesignal to supply power for the operation of the electronic device 200when the power-on signal is received at the receiving unit 300; and

a power transmission unit 111 configured to form a wireless power signalbased on the supplied DC input voltage and the drive signal to transmitwireless power to the wireless power receiver 200. The powertransmission controller 112 adjusts a transmission rate of the wirelesspower according to the power usage of the electronic device 200.

In this case, the electronic device and wireless power transmitter maybe a wireless power transmission system. The wireless power transmissionsystem may include a power supply unit configured to supply a voltage; areceiving unit configured to receive a power-on signal or power-offsignal from a remote controller; and a power transmission controllerconfigured to transmit the wireless power to the electronic device basedon the power-on signal, wherein the electronic device receives thewireless power to turn on power. The sub-power supply unit 400 is adevice for supplying low power used in the receiving unit 300.

FIG. 23 is a configuration diagram illustrating a sub-power supply unitaccording to another embodiment of the present disclosure.

As illustrated in FIG. 23, the sub-power supply unit 400 according toanother embodiment of the present disclosure may include:

a low power transmission controller 401 configured to generate a lowpower drive signal to supply low power for the operation of thereceiving unit 300;

a low power transmission unit 402 configured to convert the DC inputvoltage supplied from the power supply unit 190 to a low voltage, andform a wireless low power signal based on the converted low voltage andthe low power drive signal to transmit wireless low power; and

a low power receiving unit 403 configured to receive the wireless lowpower transmitted from the low power transmission unit 402, and supply(apply) the received wireless low power to the receiving unit 300.

The low power transmission controller has the same configuration as thatof the power transmission controller 112, but controls power to betransmitted to the receiving unit 300 which not power to be transmittedto the electronic device 200, and thus generates a drive signal fortransmitting power (low power) lower than that to be transmitted to theelectronic device 200.

The low power transmission unit has the same configuration as that ofthe power transmission unit 111, but transmits power to be transmittedto the receiving unit 300 which not power to be transmitted to theelectronic device 200, and thus it is configured to transmit power (lowpower) lower than that to be transmitted to the electronic device 200.

The low power receiving unit has the same configuration as that of thepower receiving unit 291, but receives power to be applied to thereceiving unit 300 which not power to be applied to the electronicdevice 200, and thus it is to configured to receive power (low power)lower than that to be applied to the electronic device 200.

The power transmission unit 111 of the wireless power transmitter 100may include a transmitting (Tx) coil 1111 b, an inverter 1112, and aresonant circuit 1116. The inverter 1112 may be configured to beconnected to the transmitting coil 1111 b and the resonant circuit 1116.

The transmitting coil 1111 b may be mounted separately from thetransmitting coil 1111 a for transferring power according to theinductive coupling method, but may transfer power in the inductivecoupling method and resonance coupling method using one single coil.

The transmitting coil 1111 b, as described above, forms a magnetic fieldfor transferring power. The transmitting coil 1111 b and the resonantcircuit 1116 generate resonance when alternating current power isapplied thereto, and at this time, a vibration frequency may bedetermined based on an inductance of the transmitting coil 1111 b and acapacitance of the resonant circuit 1116.

For this purpose, the inverter 1112 transforms a DC input obtained fromthe power supply unit 190 into an AC waveform, and the transformed ACcurrent is applied to the transmitting coil 1111 b and the resonantcircuit 1116.

In addition, the power transmission unit 111 may further include afrequency adjustment unit 1117 for changing a resonant frequency of thepower transmission unit 111. The resonant frequency of the powertransmission unit 111 is determined based on an inductance and/orcapacitance within a circuit constituting the power transmission unit111 by Equation 1, and thus the power transmission control unit 112 maydetermine the resonant frequency of the power transmission unit 111 bycontrolling the frequency adjustment unit 1117 to change the inductanceand/or capacitance.

According to some embodiments, the frequency adjustment unit 1117 may beconfigured to include a motor for adjusting a distance betweencapacitors included in the resonant circuit 1116 to change acapacitance. Furthermore, according to some embodiments, the frequencyadjustment unit 1117 may is include a motor for adjusting a number ofturns or diameter of the transmitting coil 1111 b to change aninductance. According to some embodiments, the frequency adjustment unit1117 may include active elements for determining the capacitance and/orinductance

The power transmission unit 111 may further include a power sensing unit1115. The operation of the power sensing unit 1115 is the same as theforegoing description.

The wireless power transmitter 100 may further include amodulation/demodulation unit 113 electrically connected to the powertransmission unit 111. The modulation/demodulation unit 113 may modulatea wireless power signal that has been modulated by the electronic device200 and use it to receive the power control message.

FIG. 24 is a flow chart illustrating a wireless power transmissionmethod for reducing standby power according to another embodiment of thepresent disclosure.

First, the power supply unit 190 supplies a DC input voltage.

The low power transmission controller 401 generates a low power drivesignal to supply low power for the operation of the receiving unit 300based on the DC input voltage (S21).

The sub-power supply unit 400 converts the DC input voltage to a lowvoltage (S22), and forms a wireless low power signal based on theconverted low voltage and the low power drive signal to generatewireless low power (S23), and applies the wireless low power to thereceiving unit 300 (S24). For example, the low power receiving unit 401generates a low power drive signal to supply low power for the operationof the receiving unit 300. The low power transmission unit 402 convertsthe DC input voltage supplied from the power supply unit 190 to a lowvoltage, and forms a wireless low power signal based on the convertedlow voltage and the low power drive signal to transmit wireless lowpower to the low power receiving unit 403. The low power receiving unit403 receives the wireless low power transmitted from the low powertransmission unit 402, and supplies (applies) the received wireless lowpower to the receiving unit 300.

The receiving unit 300 determines whether or not a power-on signal orpower-off signal is received from the remote controller 301 (S25).Accordingly, the receiving unit 300 may include the remote controlreceiver circuit. Upon receiving the power-off signal, the receivingunit 300 turns off the power transmission controller 112, therebyturning off the wireless power transmitter 100 excluding the receivingunit 300 while at the same time blocking wireless power transmitted fromthe wireless power transmitter 100 to the electronic device 200.

When a power-on signal is received from the remote controller 301, thereceiving unit 300 turns on the wireless power transmitter 100 based onthe power-on signal (S26). For example, when the power-on signal isreceived from the remote controller 301, the receiving unit 300 turns onthe power transmission controller 112 of the wireless power transmitter100 based on the power-on signal to operate the wireless powertransmitter 100. Here, the power supply unit 190 supplies a DC inputvoltage to the power transmission controller 112 when the to powertransmission controller 112 is turned on.

When the power-on signal is received at the receiving unit 300, thepower transmission controller 112 generates a drive signal to supplypower for the operation of the 200 (S27).

The power transmission unit 111 forms a wireless power signal based onis the supplied DC input voltage and the drive signal (S28) to transmitwireless power to the wireless power receiver (electronic device) 200(S29). The wireless power receiver (electronic device) 200 is operated(turned on) when receiving the wireless power.

Accordingly, according to a wireless power transmitter and a methodthereof for reducing standby power according to an embodiment of thepresent disclosure, only the receiving unit for receiving a power-on/offsignal may be turned on when the electronic device 200 to which thewireless power receiver is applied is turned off, thereby reducing thestandby power of the wireless power transmitter and the electronicdevice 200. For example, power supplied from the power supply unit 190of the wireless power transmitter 100 may be used for the consumptionpower of the receiving unit 300 when the electronic device 200 is notused, thereby reducing the standby power of the wireless powertransmitter 100 and the standby power of the electronic device 200. Inother words, when the electronic device 200 to which the wireless powerreceiver is turned off, it may be possible to reduce the standby powerof the wireless power transmitter and the standby power of theelectronic device 200 due to the sub-power supply unit 400 using powerless than that of the wireless power transmitter 100.

According to the present illustration, the electronic device andwireless power transmitter may be combined to form a wireless powertransmission system. In this case, the electronic device may include asignal receiving unit configured to receive a power-on signal orpower-off signal from a remote controller; and a power receivingcontroller configured to request the supply of wireless power to thewireless power transmitter based on the power-on signal. Here, thesignal receiving unit may be formed to receive low power having a sizeless than that of is the wireless power which is transmitted from thewireless power transmitter.

Furthermore, the power transmission generates a drive signal to supplythe wireless power to the electronic device based on the request. Then,the power receiving unit provided in the electronic device receiveswireless power transmitted in response to the request at the wirelesspower transmitter, and the power of the electronic device may be turnedon using this.

Though not shown in the drawing, according to the present disclosure,the wireless power receiver may provide a modified example with aseparate power supply unit capable of supplying power to a remotecontrol receiver circuit. In this case, the power supply unit may be abattery, a rechargeable battery, or the like, and low power can besupplied only to the remote control receiver circuit through this.

In this case, when a power-on signal is generated from the remotecontroller, the remote control receiver circuit receives the signal, andthen starts communication between the wireless power transmitter and theelectronic device. In other words, a request signal for requesting thetransmission of power may be generated and transmitted in response tothe signal reception in the wireless power receiver, and thetransmission of wireless power may be started in response to the requestsignal. The electronic device may be powered on due to the transmissionof the wireless power, thereby preventing the consumption of the standbypower in the electronic device.

The foregoing method may be implemented in a recording medium readableby a computer or its similar devices by employing, for example,software, hardware or some combinations thereof.

For a hardware implementation, the embodiments described herein may beimplemented by using at least any one of application specific integratedcircuits (ASICs), digital signal processors (DSPs), digital signalprocessing devices (DSPDs), programmable logic devices (PLDs), fieldprogrammable gate arrays (FPGAs), processors, controllers,micro-controllers, microprocessors, other electronic units designed toperform the functions described herein. For example, the foregoingmethods may be implemented by the controller 180 or power transmissioncontrol unit 112 in the wireless power transmitter 100.

For a software implementation, the embodiments such as procedures andfunctions disclosed herein may be implemented with separate softwaremodules. Each of the software modules may perform one or more of thefunctions and operations described herein. Software codes may beimplemented by using a software application written in a suitableprogramming language. The software codes may be stored in the memory 150in the wireless power transmitter 100, and implemented by the controller180 or the power transmission control unit 112.

However, it would be easily understood by those skilled in the art thatthe configuration of a wireless power transmitter according to theembodiment disclosed herein may be applicable to an apparatus, such as adocking station, a terminal cradle device, and an electronic device, andthe like, excluding a case where it is applicable to only a wirelesscharger.

The scope of the invention will not be limited to the embodimentsdisclosed herein, and thus various modifications, variations, andimprovements can be made in the present invention without departing fromthe spirit of the invention, and within the scope of the appendedclaims.

What is claimed is:
 1. A wireless power transmitter for transmittingwireless power to an electronic device to which a wireless powerreceiver is applied, the wireless power transmitter comprising: a powersupply unit configured to supply an voltage; a receiving unit configuredto receive a power-on signal or power-off signal from a remotecontroller; a power transmission controller configured to generate adrive signal to supply power for the operation of the electronic devicebased on the power-on signal; and a power transmission unit configuredto form a wireless power signal based on the supplied voltage and thedrive signal to transmit wireless power to the wireless power receiver.2. The wireless power transmitter of claim 1, wherein the receiving unitturns off the wireless power transmitter excluding the receiving unitbased on the power-off signal.
 3. The wireless power transmitter ofclaim 1, wherein the receiving unit receives power from a power supplyunit which is independent from the power supply unit.
 4. The wirelesspower transmitter of claim 1, further comprising: a sub-power supplyunit configured to apply low power used in the receiving unit.
 5. Thewireless power transmitter of claim 1, further comprising: a sub-powersupply unit configured to generate wireless low power based on thesupplied voltage, and apply the generated wireless low power to thereceiving unit.
 6. The wireless power transmitter of claim 1, furthercomprising: a sub-power supply unit configured to convert the suppliedvoltage to a low voltage, and form a wireless low power signal based onthe converted low voltage and a low power drive signal for the operationof the receiving unit to generate wireless low power, and apply thegenerated wireless low power to the receiving unit.
 7. The wirelesspower transmitter of claim 6, wherein the receiving unit receives apower-on signal or power-off signal from the remote controller based onthe wireless low power applied from the sub-power supply unit.
 8. Thewireless power transmitter of claim 6, wherein the sub-power supply unitcomprises: a low power transmission controller configured to generate alow power drive signal to supply low power for the operation of thereceiving unit; a low power transmission unit configured to convert thevoltage supplied from the power supply unit to a low voltage, and form awireless low power signal based on the converted low voltage and the lowpower drive signal to transmit wireless low power; and a low powerreceiving unit configured to receive the wireless low power transmittedfrom the low power transmission unit, and apply the received wirelesslow power to the receiving unit.
 9. The wireless power transmitter ofclaim 1, wherein the power transmission controller adjusts atransmission rate of the wireless power according to the power usage ofthe electronic device.
 10. The wireless power transmitter of claim 1,wherein the receiving unit comprises a charging device configured tocharge the wireless power output from the wireless power receiver, andsupply the charged power to the receiving unit for a period of time inwhich the wireless power transmitter is turned off.
 11. A wireless powertransmission method for transmitting wireless power to an electronicdevice to which a wireless power receiver is applied, the methodcomprising: receiving a power-on signal or power-off signal from aremote controller through a receiving unit; generating a drive signal tosupply power for the operation of the electronic device based on thepower-on signal; and forming a wireless power signal based on an inputvoltage and the drive signal to transmit wireless power to the wirelesspower receiver.
 12. The method of claim 11, wherein said receiving apower-on signal or power-off signal further comprises: turning off thewireless power transmitter based on the power-off signal.
 13. The methodof claim 11, wherein said receiving a power-on signal or power-offsignal receives the power-on signal or power-off signal based on aninput power source different from the input power.
 14. The method ofclaim 11, further comprising: applying low power used in the receivingunit.
 15. The method of claim 11, further comprising: generatingwireless low power based on the input voltage, and applying thegenerated wireless low power to the receiving unit.
 16. An electronicdevice having a wireless power receiver, the electronic devicecomprising: a signal receiving unit configured to receive a power-onsignal or power-off signal from a remote controller; a power receivingcontroller configured to request the supply of wireless power to thewireless power transmitter based on the power-on signal; and a powerreceiving unit configured to receive wireless power transmitted inresponse to the request from the wireless power transmitter to performthe power-on of the electronic device.
 17. The electronic device ofclaim 16, wherein the signal receiving unit is formed to receive lowpower having a size less than that of the wireless power which istransmitted from the wireless power transmitter.
 18. The electronicdevice of claim 17, further comprising: a power supply unit configuredto supply power to the signal receiving unit.
 19. A wireless powertransmission system having an electronic device and a wireless powertransmitter for transmitting wireless power to the electronic device,wherein the wireless power transmitter comprises: a power supply unitconfigured to supply a voltage; a receiving unit configured to receive apower-on signal or power-off signal from a remote controller; and apower transmission controller configured to transmit the wireless powerto the electronic device based on the power-on signal, wherein theelectronic device receives the wireless power to turn on power.
 20. Awireless power transmission system having an electronic device and awireless power transmitter for transmitting wireless power to theelectronic device, wherein the electronic device comprises: a signalreceiving unit configured to receive a power-on signal or power-offsignal from a remote controller; and a power receiving controllerconfigured to request the supply of wireless power to the wireless powertransmitter based on the power-on signal, wherein the wireless powertransmitter comprises: a power supply unit configured to supply an inputvoltage; and a power transmission controller configured to generate adrive signal to supply the wireless power to the electronic device basedon the request.